TCAD-ENG

SILVACO TCAD

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Starting Starting Starting Starting Starting Starting Starting Starting

DECKBUILDDECKBUILDDECKBUILDDECKBUILDDECKBUILDDECKBUILDDECKBUILDDECKBUILD

To invoke ATHENA under DECKBUILD in To invoke ATHENA under DECKBUILD in interactive mode, enter the UNIX command:interactive mode, enter the UNIX command:

deckbuild deckbuild ––an&an&

The The --anan option instructs DECKBUILD to option instructs DECKBUILD to start ATHENA as the default simulator. start ATHENA as the default simulator.

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To invoke ATHENA under DECKBUILD in To invoke ATHENA under DECKBUILD in interactive mode, enter the UNIX command:interactive mode, enter the UNIX command:

After a short delay, the main DECKBUILD After a short delay, the main DECKBUILD window will appear.window will appear.



DECKBUILD consists of DECKBUILD consists of Two sub windowsTwo sub windows::

The first window is the text window in the The first window is the text window in the upper half of the base frame. upper half of the base frame.

The lower half window is the runtime The lower half window is the runtime output window and it is used to echo the output window and it is used to echo the output of the simulator.output of the simulator.

deckbuild deckbuild ––an&an&

The The --anan option instructs DECKBUILD to option instructs DECKBUILD to start ATHENA as the default simulator. start ATHENA as the default simulator.

This text window is used to build and edit This text window is used to build and edit input files. input files.

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To become familiar with the mechanics of To become familiar with the mechanics of running running ATHENAATHENA under under DECKBUILDDECKBUILD, we , we can now load and run some of the can now load and run some of the ATHENA ATHENA standard examplesstandard examples..

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DECKBUILDDECKBUILD makes it possible to load and makes it possible to load and run a number of example simulation input run a number of example simulation input files. files.

To access the To access the ATHENAATHENA examples: examples:

Loading / Running Loading / Running Loading / Running Loading / Running Loading / Running Loading / Running Loading / Running Loading / Running

ExamplesExamplesExamplesExamplesExamplesExamplesExamplesExamples

Click on the Click on the Main ControlMain Control menu follows by menu follows by the the ExamplesExamples…… menu item.menu item.

The The Deckbuild: ExamplesDeckbuild: Examples window will window will appear.appear.

The DECKBUILDDECKBUILD examples are listed in the examples are listed in the Section menuSection menu and they are grouped and they are grouped according to the simulation topic that the according to the simulation topic that the example demonstratesexample demonstrates.

Select the Select the MOS Application ExamplesMOS Application Examples listed listed by by doubledouble--clickingclicking on this topic. on this topic.

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A list of the A list of the MOS Application ExamplesMOS Application Examples will will then be listed as shown.then be listed as shown.

Next, select the Next, select the mos1ex01.inmos1ex01.in by by doubledouble--

clickingclicking on the input file name. on the input file name.



A description of the selected input file will A description of the selected input file will appear in the examples window.appear in the examples window.

The description: The description:

a.a. lists the modules required for this lists the modules required for this example,example,

b.b. provide an overview that this example provide an overview that this example demonstrates,demonstrates,

c.c. describes the command statements describes the command statements used in this example file, used in this example file,

d. d. describes the simulated results that describes the simulated results that will be displayed in this example.will be displayed in this example.

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To load this example, press the To load this example, press the Load Load exampleexample button on the button on the top righttop right--hand hand cornercorner..



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To load this example, press the To load this example, press the Load Load exampleexample button on the top rightbutton on the top right--hand hand corner.corner.

The selected input file will then be loaded The selected input file will then be loaded into the into the DECKBUILDDECKBUILD text window. text window.



The input file, along with other files The input file, along with other files associated with the input file will be copied associated with the input file will be copied into your working directory.into your working directory.

You can now run the input file by pressing You can now run the input file by pressing the the runrun button on the button on the DECKBUILD ControlDECKBUILD Control. .

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Once the process simulation has Once the process simulation has completed, the MOSFET structure will be completed, the MOSFET structure will be automatically plotted as shown.automatically plotted as shown.



This MOS structure will then automatically This MOS structure will then automatically passed to the device simulator, ATLAS for passed to the device simulator, ATLAS for device simulation.device simulation.

Once the simulation is completed, Once the simulation is completed, TONYPLOTTONYPLOT will then display the Idwill then display the Id--Vg Vg characteristics of the MOSFET device.characteristics of the MOSFET device.

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Creating A Typical NMOS Input Deck FileCreating A Typical NMOS Input Deck FileCreating A Typical NMOS Input Deck FileCreating A Typical NMOS Input Deck FileCreating A Typical NMOS Input Deck FileCreating A Typical NMOS Input Deck FileCreating A Typical NMOS Input Deck FileCreating A Typical NMOS Input Deck File

In this session, we will learn the basic operations required forIn this session, we will learn the basic operations required for creating creating a typical MOSFET input file.a typical MOSFET input file.

These operations include:These operations include:

•• Developing a good simulation gridDeveloping a good simulation grid

•• Performing conformal deposition and geometric etchPerforming conformal deposition and geometric etch

•• Performing oxidation, ion implantation and annealingPerforming oxidation, ion implantation and annealing

•• Extracting and Optimizing process parametersExtracting and Optimizing process parameters

•• Saving and loading structure informationSaving and loading structure information

These operations are relevant to all individual ATHENA process These operations are relevant to all individual ATHENA process simulators. simulators.

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Creating An Creating An Creating An Creating An Creating An Creating An Creating An Creating An

Initial Structure Initial Structure Initial Structure Initial Structure Initial Structure Initial Structure Initial Structure Initial Structure

Before creating the initial structure, we Before creating the initial structure, we need to clear the current text window of need to clear the current text window of DECKBUILD by pulling down the DECKBUILD by pulling down the FileFile menu menu follows by follows by Empty DocumentEmpty Document..

The The Deckbuild: Main ControlDeckbuild: Main Control popup window popup window will appearswill appears

Next, we will also clear the Next, we will also clear the history fileshistory files that that were automatically created during the MOS were automatically created during the MOS example simulation. To do so,example simulation. To do so,

Select the Select the Main ControlMain Control menu, follows by menu, follows by Main ControlMain Control……

Then, click on the Then, click on the History PropsHistory Props……

The text window is now empty.The text window is now empty.

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This invokes the This invokes the History PropertiesHistory Propertieswindow. window.

Once finished, close the Once finished, close the History popupHistory popup by by clicking on the top left hand corner and clicking on the top left hand corner and select select CloseClose. .

Next, click on the Next, click on the clear clear button to clear the button to clear the history file.history file.

The The lineslines will now be reset to will now be reset to 00 which which means that the history files have been means that the history files have been cleared.cleared.

Close the Close the Main ControlMain Control popup as well by popup as well by clicking on the top left hand corner and clicking on the top left hand corner and select select CloseClose. .

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To start To start ATHENAATHENA as the simulator, we need as the simulator, we need to start off with the to start off with the ““gogo”” statement by statement by typing the statement: typing the statement:

go athenago athena

in the text window.in the text window.

The correct specification of a grid is critical The correct specification of a grid is critical in process simulation. in process simulation.

Now, we can start defining the initial Now, we can start defining the initial rectangular grid. rectangular grid.



The number of nodes in the grid has a The number of nodes in the grid has a direct influence on simulation accuracy and direct influence on simulation accuracy and time. time.

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The The Mesh DefineMesh Define menu will appear. menu will appear.

To define the rectangular grid, from the To define the rectangular grid, from the CommandsCommands menu, select the menu, select the Mesh Define...Mesh Define...menu item. menu item.

From the From the Mesh DefineMesh Define menu, the menu, the DirectionDirectionfield is selected as field is selected as X X by default. by default.

Also, the default value of the Also, the default value of the LocationLocation field field is is 00 and and 0.10.1 for the for the SpacingSpacing field.field.

For the For the Comment Comment field,field, type type NonNon--Uniform Uniform Grid (0.6um x 0.8um)Grid (0.6um x 0.8um)



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In the same way, set the location of a In the same way, set the location of a second X line to second X line to 0.20.2 with a spacing of with a spacing of 0.010.01and a third X line to and a third X line to 0.60.6 with a spacing of with a spacing of 0.010.01. .

Next, click on the Next, click on the InsertInsert button in the button in the Mesh Mesh

DefineDefine window and the line parameters will window and the line parameters will appear in the scrolling list. appear in the scrolling list.



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Click on the Click on the LocationLocation field and enter a field and enter a value of value of 00. .

Next, we shall proceed to create the grid in Next, we shall proceed to create the grid in the Y direction. Select the Y direction. Select YY in the Direction in the Direction field.field.

Then, click on the Then, click on the SpacingSpacing field and enter a field and enter a value of value of 0.0080.008. .

Click on the Click on the Insert Insert button in the button in the Mesh Mesh

DefineDefine window.window.

In the same way, set the: In the same way, set the:

22ndnd Y line Location to Y line Location to 0.20.2, Spacing of , Spacing of 0.010.01

33rdrd Y line Location to Y line Location to 0.50.5, Spacing of , Spacing of 0.050.05

44thth Y line Location to Y line Location to 0.80.8, Spacing of , Spacing of 0.150.15..



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Notice that the finest grid is defined at the Notice that the finest grid is defined at the surface from location y=0surface from location y=0µµµµµµµµm to y=0.2m to y=0.2µµµµµµµµm. m.

This region will later be use to form the This region will later be use to form the surface active region of the NMOS surface active region of the NMOS transistor. transistor.

To preview the rectangular grid, from the To preview the rectangular grid, from the Mesh DefineMesh Define menu, click on the menu, click on the View...View...button. button.

The The View GridView Grid window will be displayed. window will be displayed. (Notice that a total of (Notice that a total of 1786 points1786 points and and 3404 3404 trianglestriangles are generated.)are generated.)

Close the Close the View GridView Grid Window after viewing.Window after viewing.



Therefore, it is essential to have finest grid Therefore, it is essential to have finest grid in this region. in this region.

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And press the And press the WRITEWRITE button to write the button to write the mesh define information into the text mesh define information into the text window.window.

A set of lines will appear as shown.A set of lines will appear as shown.

It is a good practice to save the file It is a good practice to save the file frequently to avoid loss of data. To save the frequently to avoid loss of data. To save the input file:input file:

Click on the Click on the FileFile menu, follows by menu, follows by SaveSave

The The Save AsSave As popup will appear.popup will appear.

KeyKey--in the file name as in the file name as ““nmos.innmos.in”” and click and click on the on the SaveSave button.button.

The file is now saved as The file is now saved as ““nmos.innmos.in””..



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The The LINELINE statements specified by the statements specified by the Mesh Mesh

DefineDefine menu set only the rectangular base menu set only the rectangular base for the ATHENA simulation structure.for the ATHENA simulation structure.

The next step is the initialization of the The next step is the initialization of the substrate region. substrate region.

To initialize the simulation structure: To initialize the simulation structure:

From the ATHENA From the ATHENA CommandsCommands menu, select menu, select Mesh InitializeMesh Initialize……

The The ATHENA ATHENA Mesh InitializeMesh Initialize menu will menu will popup.popup.



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By default, By default, SiliconSilicon is selected as the is selected as the Material with Material with <100><100> Orientation.Orientation.

Click on the Click on the BoronBoron impurity box so that impurity box so that Boron is selected as the background Boron is selected as the background doping. doping.

For the For the ConcentrationConcentration field, select the field, select the desired concentration as desired concentration as 1.01.0 using the using the slider or by typing it, and select an slider or by typing it, and select an exponent of exponent of 1414 from the from the Exp:Exp: field. field.

This will give a background concentration This will give a background concentration of 1.0 x 10of 1.0 x 101414 atom/cmatom/cm33. .

For the For the DimensionalityDimensionality field, check the field, check the 2D2Dbox. This forces the simulation to be run in box. This forces the simulation to be run in a twoa two--dimensional calculation.dimensional calculation.



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For the For the CommentComment field, type field, type ““Initial Silicon Initial Silicon Structure with <100> OrientationStructure with <100> Orientation””..

Press the Press the WRITEWRITE button to write the button to write the initialization information into the text initialization information into the text window. window.



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For the For the CommentComment field, type field, type ““Initial Silicon Initial Silicon Structure with <100> OrientationStructure with <100> Orientation””..

Press the Press the WRITEWRITE button to write the button to write the initialization information into the text initialization information into the text window. window.

The following The following CommentComment and and InitializeInitialize

statements will appear in the text window:statements will appear in the text window:

#Initial Silicon Structure with <100> #Initial Silicon Structure with <100> OrientationOrientationinit silicon c.boron=1.0e14 orientation=100 init silicon c.boron=1.0e14 orientation=100 two.d two.d



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Now, run ATHENA to obtain the initial Now, run ATHENA to obtain the initial structure by clicking on the structure by clicking on the runrun button and button and DECKBUILD will start executing the DECKBUILD will start executing the command lines.command lines.

Once DECKBUILD finishes executing the Once DECKBUILD finishes executing the lines, the line lines, the line struct outfile=.history01.strstruct outfile=.history01.str is is automatically produced by the History automatically produced by the History function as shown.function as shown.

This is the initial structure file and to This is the initial structure file and to visualize it: visualize it:

Highlight the Highlight the ““.history01.str.history01.str”” file. file.



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Next, pull down the Next, pull down the ToolsTools menu, select menu, select Plot Plot follows by follows by Plot Structure...Plot Structure...

After a short delay, TONYPLOT will appear. After a short delay, TONYPLOT will appear.

It will have only regional and material It will have only regional and material information. To display the mesh information. To display the mesh information:information:

From TONYPLOT, pull down the From TONYPLOT, pull down the PlotPlot menu, menu, followed byfollowed by Display Display ……. .

The The Display (2D Mesh)Display (2D Mesh) menu will appear.menu will appear.

By default, the By default, the EdgesEdges and and RegionsRegions icons icons will be selected. Click on the will be selected. Click on the MeshMesh icon, icon, follows by the follows by the ApplyApply button. button.



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And then click on the And then click on the DismissDismiss button. button.

The initial triangular grid will appears as The initial triangular grid will appears as shown.shown.

So, the previousSo, the previous INITINIT statement creates a statement creates a <100> silicon region of size 0.6um x 0.8um, <100> silicon region of size 0.6um x 0.8um, which is uniformly doped with boron which is uniformly doped with boron concentration of 1 x 10concentration of 1 x 101414 atom/cmatom/cm33. .

This simulation structure is ready for any This simulation structure is ready for any process step (e.g. ion implantation, process step (e.g. ion implantation, diffusion, oxidation, etc.).diffusion, oxidation, etc.).

After viewing the initial structure, we can After viewing the initial structure, we can now quit from TONYPLOT by clicking on now quit from TONYPLOT by clicking on the topthe top--left hand corner follows by left hand corner follows by CloseClose..



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Next, we will grow an gate oxide layer on Next, we will grow an gate oxide layer on the Silicon surface by performing dry the Silicon surface by performing dry oxidation at 950 oxidation at 950 ooC for 11 minutes in 3% C for 11 minutes in 3% HCL at 1.0 atmospheric pressure. HCL at 1.0 atmospheric pressure.

To perform this gate oxidation step, from To perform this gate oxidation step, from the ATHENAthe ATHENA CommandsCommands menu, select the menu, select the items items ProcessProcess ⇒⇒⇒⇒⇒⇒⇒⇒ Diffuse...Diffuse.... .

The The ATHENA ATHENA DiffuseDiffuse menu will appear as menu will appear as shown. shown.

Performing Gate Performing Gate Performing Gate Performing Gate Performing Gate Performing Gate Performing Gate Performing Gate

Oxidation Oxidation Oxidation Oxidation Oxidation Oxidation Oxidation Oxidation

From the From the DiffuseDiffuse Menu, change the Menu, change the Time Time (minutes)(minutes) from from 3030 to to 1111 and the and the Temperature (C)Temperature (C) from from 10001000 to to 950950. .

From the From the Ambient Ambient field, click on the field, click on the Dry O2Dry O2box. box.

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Check on the Check on the Gas pressure (atm)Gas pressure (atm) and the and the HCL %HCL % fields. Change the HCL tofields. Change the HCL to 33%. %.

Add a comment Add a comment ““Gate OxidationGate Oxidation”” in the in the CommentComment field and click on the field and click on the WRITEWRITEbutton.button.

The gate oxidation information will be The gate oxidation information will be written into DECKBUILD text window as written into DECKBUILD text window as shown by the shown by the DiffuseDiffuse statement:statement:

# Gate Oxidation# Gate Oxidationdiffus time=11 temp=950 dryo2 press=1.00 diffus time=11 temp=950 dryo2 press=1.00 hcl.pc=3hcl.pc=3



Continue the ATHENA simulation by Continue the ATHENA simulation by clicking on the clicking on the ContCont button on the button on the DECKBUILD control. DECKBUILD control.

Once the gate oxidation step is completed, Once the gate oxidation step is completed, another history file another history file ““.history02.str.history02.str”” will be will be saved as shown. saved as shown.

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Plot this structure again by highlighting Plot this structure again by highlighting ““.history02.str.history02.str”” file.file.

Then, pull down the Then, pull down the Tools Tools menu and select menu and select the the PlotPlot follows by follows by Plot Structure...Plot Structure...

The resulting gate oxide structure will The resulting gate oxide structure will appears in TONYPLOT as shown. appears in TONYPLOT as shown.



From the plot, it can be seen that an oxide From the plot, it can be seen that an oxide layer was deposited onto the silicon layer was deposited onto the silicon surface. surface.

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Next, we would like to extract the gate Next, we would like to extract the gate oxide thickness that was grown during the oxide thickness that was grown during the oxidation process step. oxidation process step.

This can be done using the This can be done using the ExtractExtract routines routines of DECKBUILD.of DECKBUILD.

ExtractExtract forms a forms a ““function calculatorfunction calculator”” that that allows you to combine and manipulate allows you to combine and manipulate values or entire curves quickly and easily. values or entire curves quickly and easily.

Extracting Gate Extracting Gate Extracting Gate Extracting Gate Extracting Gate Extracting Gate Extracting Gate Extracting Gate

Oxide Thickness Oxide Thickness Oxide Thickness Oxide Thickness Oxide Thickness Oxide Thickness Oxide Thickness Oxide Thickness

You can create your own, customized You can create your own, customized expressions, or choose from a number of expressions, or choose from a number of standard routines provided for the process standard routines provided for the process and device simulators. and device simulators.

To extract the thickness of gate oxide: To extract the thickness of gate oxide:

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First, we can First, we can closeclose the TONYPLOT.the TONYPLOT.

Next, pull down the Next, pull down the CommandsCommands menu and menu and click on click on ExtractExtract…….. as shown. as shown.

The The ATHENA ExtractATHENA Extract menu will appears.menu will appears.



By default, the By default, the Material thicknessMaterial thickness is is selected in the selected in the ExtractExtract field. field.

For the For the NameName field, type in field, type in ““GateoxideGateoxide””. .

For the For the MaterialMaterial field, click on the field, click on the MaterialMaterial…… button. button.

The The Material ChooserMaterial Chooser popup will appear. popup will appear.

By default, By default, SiliconSilicon is selected. Since we are is selected. Since we are extracting the oxide thickness, therefore extracting the oxide thickness, therefore change it to change it to SiO~2SiO~2 and click and click ApplyApply..

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Next, in the Next, in the Extract locationExtract location field, the field, the X X location is selected by default and enter a location is selected by default and enter a value of value of 0.30.3..

Click on the Click on the WRITEWRITE button when done.button when done.



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Next, in the Next, in the Extract locationExtract location field, the field, the X X location is selected by default and enter a location is selected by default and enter a value of value of 0.30.3..




The The ExtractExtract statement will appear in the statement will appear in the text window as shown. text window as shown.

In this In this ExtractExtract statement, all the parameters statement, all the parameters are selfare self--explanatory except the explanatory except the mat.occno=1mat.occno=1 which specifies the layer which specifies the layer occurrence number. occurrence number.

This parameter is optional in this case as This parameter is optional in this case as there is only one silicon dioxide layer. there is only one silicon dioxide layer.

However, in some cases where there are However, in some cases where there are many stacked silicon dioxide layers, we many stacked silicon dioxide layers, we have to specify the specific silicon dioxide have to specify the specific silicon dioxide layer that we are interested in. layer that we are interested in.

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Continue the ATHENA simulation by Continue the ATHENA simulation by clicking on the clicking on the ContCont button on the button on the DECKBUILD control. DECKBUILD control.

The runtime output of the The runtime output of the ExtractExtract statement statement will then appear as shown.will then appear as shown.



Thus, we can see that the extracted gate Thus, we can see that the extracted gate oxide thickness was oxide thickness was 131.347 131.347 ÅÅ. .

In the next section, we shall learn how to In the next section, we shall learn how to optimize this extracted gate oxide optimize this extracted gate oxide thickness.thickness.

It can be seen that the current structure is It can be seen that the current structure is first saved in a first saved in a /tmp/tmp folder and it is being folder and it is being called out by called out by Extract Extract to perform parameters to perform parameters extraction. extraction.

When the extraction is done, When the extraction is done, ExtractExtract will will automatically automatically quit quit and and ATHENAATHENA is invoked is invoked again.again.

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In this section, we will learn how to use the In this section, we will learn how to use the Optimizer functionOptimizer function in DECKBUILD to in DECKBUILD to optimize the gate oxidation process optimize the gate oxidation process parameters. parameters.

Assuming that the measured gate oxide Assuming that the measured gate oxide thickness is thickness is 100100ÅÅ, and both the , and both the temperaturetemperature and and partial pressurepartial pressure in the in the Gate OxidationGate Oxidation step need to be tuned. step need to be tuned.

OptimizingOptimizingOptimizingOptimizingOptimizingOptimizingOptimizingOptimizing Gate Gate Gate Gate Gate Gate Gate Gate


To optimize this parameter, pull down the To optimize this parameter, pull down the Main ControlMain Control menu and select the menu and select the OptimizerOptimizer……

This invokes the DECKBUILD This invokes the DECKBUILD Optimizer Optimizer as as shown.shown.

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In the In the SetupSetup Mode, the optimizer displays a Mode, the optimizer displays a table of the control parameters. table of the control parameters.

The default parameters here are normally The default parameters here are normally adequate, except that we can set the adequate, except that we can set the Maximum error (%)Maximum error (%) so as to fine tune the so as to fine tune the gate oxide thickness to gate oxide thickness to 100100ÅÅ..



Therefore, change the value of Therefore, change the value of Maximum Maximum Error (%)Error (%) on the on the Stop criteriaStop criteria column from column from 55 to to 11..

And now we can proceed to define the And now we can proceed to define the parameter to be optimized. parameter to be optimized.

To do so, pull down the To do so, pull down the ModeMode menu and menu and select the select the Parameters Parameters Mode as shown.Mode as shown.

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For this workshop, the optimization For this workshop, the optimization parameters are the parameters are the temperaturetemperature and and partial partial pressurepressure during the during the Gate OxidationGate Oxidation step. step.

To define these parameters, go to To define these parameters, go to DECKBUILDDECKBUILD window and highlight thewindow and highlight the Gate Gate

OxidationOxidation step as shown.step as shown.



Then, within the Then, within the OptimizerOptimizer, pull down the , pull down the Edit Edit menu and select the menu and select the AddAdd item. item.

The The Deckbuild: Parameter defineDeckbuild: Parameter define popup popup window will then appear as shown.window will then appear as shown.

Check on the Check on the temp=<variable>temp=<variable> and and press=<variable>press=<variable> items.items.

Then, click on the Then, click on the ApplyApply button. button.

This window lists the items that may be This window lists the items that may be used as the used as the optimizing parametersoptimizing parameters in the in the Diffuse Diffuse statement.statement.

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Close the Close the Parameter defineParameter define window by window by doubledouble--clicking on the top leftclicking on the top left--hand corner. hand corner.

The added optimization parameters will The added optimization parameters will then be display as shown.then be display as shown.



Next, pull down the Next, pull down the ModeMode menu and change menu and change it to it to TargetsTargets mode so as to define the mode so as to define the optimization target. optimization target.

As the As the OptimizerOptimizer will be using the value of will be using the value of ExtractExtract statement to define the statement to define the Optimization TargetOptimization Target, therefore, go to text , therefore, go to text window and highlight the window and highlight the Extract Extract statement statement as shown. as shown.

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Then, within the Then, within the OptimizerOptimizer, pull down the , pull down the Edit Edit menu follows by the menu follows by the AddAdd item. item.

This adds the target This adds the target ““GateoxideGateoxide”” to the to the Optimizer target listOptimizer target list..



Next, enter a value of Next, enter a value of 100100ÅÅ for the for the Target Target valuevalue and hit theand hit the [RETURN] [RETURN] button on the button on the keyboardkeyboard after editing the target value.after editing the target value.

Therefore, Therefore, OptimizerOptimizer has now been has now been configured to optimize the gate oxide configured to optimize the gate oxide thickness by varying the thickness by varying the temperaturetemperature and and partial pressurepartial pressure during the during the Gate OxidationGate Oxidation

process step. process step.

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To monitor the optimization process, To monitor the optimization process, change from change from TargetsTargets mode to mode to Graphics Graphics mode as shown.mode as shown.

Finally, to perform optimization, click on Finally, to perform optimization, click on the the OptimizeOptimize button. button.



The simulation will run again and will, after The simulation will run again and will, after a little time, start to iterate the a little time, start to iterate the Gate Gate

OxidationOxidation step. step.

The Optimizer will then converged at a The Optimizer will then converged at a temperature of temperature of 925.727925.727 ooCC and a partial and a partial pressure of pressure of 0.9829790.982979 and the extracted and the extracted oxide thickness is oxide thickness is 100.209100.209ÅÅ..

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To complete this optimizationTo complete this optimization exercise, the exercise, the optimized valueoptimized value for the for the temperaturetemperature and and partial pressurepartial pressure should be copied back to should be copied back to the input deck. the input deck.



To copy this value, go to the To copy this value, go to the Parameters Parameters mode.mode.

Then, pull down the Then, pull down the EditEdit menu follows by menu follows by Copy to DeckCopy to Deck to update the optimized to update the optimized parameter in the input deck. parameter in the input deck.

The input deck will be automatically The input deck will be automatically updated in the correct place. updated in the correct place.

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Ion implantation is the main method used Ion implantation is the main method used to introduce doping impurities into to introduce doping impurities into semiconductor device structures. semiconductor device structures.

Performing Ion Performing Ion Performing Ion Performing Ion Performing Ion Performing Ion Performing Ion Performing Ion

Implantation Implantation Implantation Implantation Implantation Implantation Implantation Implantation

Adequate simulation of the ion implantation Adequate simulation of the ion implantation process is very important because modern process is very important because modern technologies employ shallow doping technologies employ shallow doping profiles, high doses, tilted implants and profiles, high doses, tilted implants and other advanced methods.other advanced methods.

In ATHENA, ion implementation is done In ATHENA, ion implementation is done using the using the IMPLANTIMPLANT statement which can be statement which can be set using the set using the ATHENA ImplantATHENA Implant menu. menu.

In this tutorial, we will perform a In this tutorial, we will perform a Threshold Threshold Voltage Adjust ImplantVoltage Adjust Implant using Boron with a using Boron with a dose of 9.5 x 10dose of 9.5 x 101111 cmcm--22 at an energy of 10 at an energy of 10 keV, with the ion beam tilted at 7keV, with the ion beam tilted at 7oo and and rotated at 30rotated at 30oo..

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To do so, pull down the To do so, pull down the CommandsCommands menu menu and select and select ProcessProcess follows by follows by Implant...Implant...



The The ATHENA ImplantATHENA Implant menu will appears as menu will appears as shown.shown.

Enter a value of Enter a value of 9.59.5 in the in the DoseDose field using field using the slider or by typing it. the slider or by typing it.

Also, ensure that the default exponent Also, ensure that the default exponent value in the value in the Exp:Exp: field is field is 1111..

In theIn the Impurity Impurity field , field , ““BoronBoron”” is by default is by default selected.selected.

Then, enter a value of Then, enter a value of 10 10 for the for the EnergyEnergyfield, field, 77 for the for the TiltTilt field and field and 3030 for the for the RotationRotation field.field.

For the implant For the implant ModelModel, the , the Dual PearsonDual Pearsonmodel is selected by default.model is selected by default.

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Finally, type the comment Finally, type the comment Threshold Threshold Voltage Adjust implantVoltage Adjust implant in the in the CommentCommentfield.field.



Click on the Click on the WRITEWRITE button.button.

All the parameters in the All the parameters in the Implant Implant statement statement are selfare self--explanatory except the explanatory except the CRYSTALCRYSTALparameter.parameter.

Press on the Press on the ContCont button and ATHENA will button and ATHENA will continue the simulation and output another continue the simulation and output another history file history file ““.history05.str.history05.str””..

And the And the ImplantImplant statements will appear in statements will appear in the text window as shown.the text window as shown.

This parameter specify the This parameter specify the SIMS Verified SIMS Verified Dual PearsonDual Pearson ((SVDPSVDP) moments tables to be ) moments tables to be used for the silicon implant ranges for theused for the silicon implant ranges for theDual PearsonDual Pearson ImplantImplant model.model.

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This can be done using the This can be done using the 2D Mesh menu2D Mesh menu

or using the or using the Cutline toolCutline tool of TONYPLOT. of TONYPLOT.

Analyzing Boron Analyzing Boron Analyzing Boron Analyzing Boron Analyzing Boron Analyzing Boron Analyzing Boron Analyzing Boron

Doping ProfileDoping ProfileDoping ProfileDoping ProfileDoping ProfileDoping ProfileDoping ProfileDoping Profile

In the In the 2D Mesh menu2D Mesh menu, we can obtain the , we can obtain the contour plot of the Boron doping profile.contour plot of the Boron doping profile.

First, we shall illustrate the use of the First, we shall illustrate the use of the 2D 2D

Mesh menuMesh menu to obtain the Boron doping to obtain the Boron doping profile. profile.

To do so, plot the history file To do so, plot the history file ““.history05.str.history05.str”” of the of the threshold voltage threshold voltage adjust implantadjust implant step by step by highlightinghighlighting it.it.

On the other hand, performing a On the other hand, performing a CutlineCutline on on the 2D structure create a 1D crossthe 2D structure create a 1D cross--section section plot of the doping profile. plot of the doping profile.

Next, we will analyze the doping profile of Next, we will analyze the doping profile of the implanted Boron in TONYPLOT.the implanted Boron in TONYPLOT.

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Then, pull down the Then, pull down the ToolsTools menu and select menu and select Plot Plot follows byfollows by Plot Structure...Plot Structure...



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Then, pull down the Then, pull down the ToolsTools menu and select menu and select Plot Plot follows byfollows by Plot Structure...Plot Structure...



TONYPLOT will appears. TONYPLOT will appears.

Click on the Click on the ContoursContours icon to plot the icon to plot the contour of the structure.contour of the structure.

Then, pull down the Then, pull down the DefineDefine menu and select menu and select ContoursContours…… as shown.as shown.

From TONYPLOT, pull down the From TONYPLOT, pull down the PlotPlot menu menu and select and select DisplayDisplay……

The The Display (2D Mesh)Display (2D Mesh) popup will appear.popup will appear.

The The TONYPLOT: ContoursTONYPLOT: Contours popup will popup will appears. appears.

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By default, By default, Net dopingNet doping is being selected in is being selected in the the QuantityQuantity option of the popup. option of the popup.



Next, we shall perform a Next, we shall perform a cutlinecutline on the 2D on the 2D structure to create a structure to create a 1D cross section plot1D cross section plotof the Boron doping profile. of the Boron doping profile.

Click on the Click on the Apply Apply button follows by the button follows by the DismissDismiss button when finished and another button when finished and another DismissDismiss button.button.

The The contour plotcontour plot of the Boron doping of the Boron doping profile will appears as shown.profile will appears as shown.

Pull down the Pull down the QuantityQuantity menu and change it menu and change it to to BoronBoron. .

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To do so, from TONYPLOT, pull down the To do so, from TONYPLOT, pull down the Tools Tools menu follows by menu follows by CutlineCutline……..



In this way, a 1In this way, a 1--D cross section plot of the D cross section plot of the Boron doping profile will appears in Boron doping profile will appears in another window as shown.another window as shown.

The The CutlineCutline popup will appear. popup will appear.

In the structure plot, In the structure plot, left clickleft click and and dragdrag the the mouse starting from the oxide layer to the mouse starting from the oxide layer to the bottom of the structure. bottom of the structure.

This will restrict the cutline to a vertical This will restrict the cutline to a vertical direction.direction.

By default, the By default, the VerticalVertical icon is selected. icon is selected.

As can be seen from this cross sectional As can be seen from this cross sectional plot, the plot, the Concentration Concentration of the Implanted of the Implanted Boron is plotted against the Boron is plotted against the DepthDepth of the of the device.device.

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Next, we shall proceed to perform the Next, we shall proceed to perform the conformal deposition for the polysilicon conformal deposition for the polysilicon gate. gate.

Deposition for Deposition for Deposition for Deposition for Deposition for Deposition for Deposition for Deposition for

Polysilicon Gate Polysilicon Gate Polysilicon Gate Polysilicon Gate Polysilicon Gate Polysilicon Gate Polysilicon Gate Polysilicon Gate

Then, to set the conformal deposition step, Then, to set the conformal deposition step, pull down the pull down the CommandsCommands menu and select menu and select the items the items Process Process ⇒⇒⇒⇒⇒⇒⇒⇒ DepositDeposit ⇒⇒⇒⇒⇒⇒⇒⇒ Deposit... Deposit...

Knowing that the polysilicon layer Knowing that the polysilicon layer thickness grown in the NMOS process is thickness grown in the NMOS process is 2000 Angstroms2000 Angstroms, it is possible to substitute , it is possible to substitute this with conformal polysilicon deposition. this with conformal polysilicon deposition.

We can now close TONYPLOT by clicking We can now close TONYPLOT by clicking on the top right hand corner and select on the top right hand corner and select CloseClose..

It is the simplest deposit model and can be It is the simplest deposit model and can be used in all cases when the exact shape of used in all cases when the exact shape of the deposited layer is not critical. the deposited layer is not critical.

Conformal deposition can be used to Conformal deposition can be used to generate multilayered structures. generate multilayered structures.

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The ATHENA The ATHENA Deposit Deposit menu will appear. menu will appear.



It is always useful to set It is always useful to set several grid layersseveral grid layersin a deposited layer. in a deposited layer.

In the In the MaterialMaterial field, field, PolysiliconPolysilicon is also is also selected. selected.

In the In the Grid specificationGrid specification parameters, click parameters, click on the on the ““Total number of grid layersTotal number of grid layers””checkbox and set its value to checkbox and set its value to 1010. .

From the From the DepositDeposit Menu, the Menu, the Conformal Conformal deposition is the selected by default. deposition is the selected by default.

Set its Set its thicknessthickness to to 0.20.2..

In this case, In this case, 10 grid layers10 grid layers are needed in are needed in order to simulate impurity transport order to simulate impurity transport through the polysilicon layer which will be through the polysilicon layer which will be shown later.shown later.

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Add a comment Add a comment ““Conformal Polysilicon Conformal Polysilicon DepositionDeposition”” in the Comment field and click in the Comment field and click on the on the WRITE WRITE button. button.



The following lines will appear in the text The following lines will appear in the text window:window:

# Conformal Polysilicon Deposition# Conformal Polysilicon Depositiondeposit polysilicon thick=0.2 divisions=10deposit polysilicon thick=0.2 divisions=10

Highlight this structure again by selecting Highlight this structure again by selecting the menu items the menu items Plot Plot ⇒⇒⇒⇒⇒⇒⇒⇒ Plot Structure..Plot Structure.... .. from the from the ToolsTools menu of DECKBUILD.menu of DECKBUILD.

Continue the ATHENA simulation using the Continue the ATHENA simulation using the Cont Cont button on the DECKBUILD control. button on the DECKBUILD control.

““history06.strhistory06.str”” structure file is produced structure file is produced once deposit step is completed.once deposit step is completed.

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A three layers structure is created as A three layers structure is created as shown.shown.



After viewing, After viewing, closeclose TONYPLOT.TONYPLOT.

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After depositing the polysilicon, the next After depositing the polysilicon, the next step in the process simulation is the step in the process simulation is the polysilicon gate definition. polysilicon gate definition.


Definition Definition Definition Definition Definition Definition Definition Definition

In this tutorial, we will use a polysilicon In this tutorial, we will use a polysilicon gate edge at x = 0.35 gate edge at x = 0.35 µµµµµµµµm and set the center m and set the center of the gate at x = 0.6 of the gate at x = 0.6 µµµµµµµµm for the initial grid. m for the initial grid.

Therefore, polysilicon should be etched to Therefore, polysilicon should be etched to the left from x = 0.35.the left from x = 0.35.

EtchedEtched

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To define the polysilicon gate, pull down To define the polysilicon gate, pull down the the CommandsCommands menu and select the items menu and select the items ProcessProcess ⇒⇒⇒⇒⇒⇒⇒⇒ EtchEtch ⇒⇒⇒⇒⇒⇒⇒⇒ Etch....Etch....

EtchedEtched

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The The ATHENA EtchATHENA Etch menu will appears as menu will appears as shown. shown.


To define the polysilicon gate, pull down To define the polysilicon gate, pull down the the CommandsCommands menu and select the items menu and select the items ProcessProcess ⇒⇒⇒⇒⇒⇒⇒⇒ EtchEtch ⇒⇒⇒⇒⇒⇒⇒⇒ Etch....Etch....

From the From the EtchEtch menu, click on menu, click on ““LeftLeft”” for the for the Geometrical typeGeometrical type field.field.

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Next, pull down the Next, pull down the MaterialMaterial menu and menu and select the material select the material PolysiliconPolysilicon. .



Set the Set the EtchEtch location to location to 0.350.35. .

# Poly Definition# Poly Definitionetch polysilicon left p1.x=0.35etch polysilicon left p1.x=0.35

Add the comment Add the comment ““Poly DefinitionPoly Definition”” for the for the CommentComment field. field.

Click on the Click on the WRITEWRITE button and this will give button and this will give the following statement: the following statement:

Continue the ATHENAContinue the ATHENA simulation using the simulation using the Cont Cont button and plot the etched structure.button and plot the etched structure.

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After defining the polysilicon gate, the next After defining the polysilicon gate, the next step is to perform polysilicon oxidation step is to perform polysilicon oxidation prior to doping of the polysilicon by ion prior to doping of the polysilicon by ion implantation. implantation.

Polysilicon Polysilicon Polysilicon Polysilicon Polysilicon Polysilicon Polysilicon Polysilicon


The oxidation recipe will be a wet oxidation The oxidation recipe will be a wet oxidation for for 3 minutes3 minutes at at 900900ooCC and and 1 Atmospheric 1 Atmospheric pressurepressure. .

The The fermifermi method is used for undamaged method is used for undamaged substrates with doping concentrations < substrates with doping concentrations < 1x101x1020 20 cmcm--33..

Since the oxidation is on a patterned (nonSince the oxidation is on a patterned (non--planar) and undamaged polysilicon, the planar) and undamaged polysilicon, the method used will be the method used will be the fermifermi and and compresscompress methods. methods.

whereas the whereas the compresscompress method is used to method is used to model oxidation on nonmodel oxidation on non--planar structures planar structures and for 2and for 2--D oxidation. D oxidation.

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To perform this oxidation step, the To perform this oxidation step, the DiffuseDiffusemenu is used.menu is used.



Invoke this menu by pulling down the Invoke this menu by pulling down the ATHENA ATHENA CommandsCommands menu and select the menu and select the items items Process Process ⇒⇒⇒⇒⇒⇒⇒⇒ Diffuse....Diffuse....

From theFrom the AmbientAmbient field, click on the field, click on the Wet O2Wet O2box.box.

The The DiffuseDiffuse menu will appear.menu will appear.

From the From the DiffuseDiffuse Menu, change the Menu, change the Time Time from from 11 11 toto 33 and the and the TemperatureTemperature from from 950 950 to to 900900. .

UncheckUncheck the the HCL HCL checkbox. checkbox.

Click on the Click on the ModelsModels setting from the setting from the Display Display field. The models available will then field. The models available will then be displayed. be displayed.

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Check on the Check on the Diffusion Diffusion model as well as the model as well as the Oxidation Oxidation models.models.


The The FermiFermi and and CompressibleCompressible boxes are by boxes are by default selected. default selected.

Change the comment in the Change the comment in the CommentComment field field to to ““Polysilicon OxidationPolysilicon Oxidation””. .

And the following And the following DiffuseDiffuse statement will statement will then be added into the input file: then be added into the input file:

# Polysilicon Oxidation# Polysilicon Oxidationmethod fermi compressmethod fermi compressdiffus time=3 temp=900 weto2 press=1.00diffus time=3 temp=900 weto2 press=1.00

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Continue the simulation using the Continue the simulation using the Cont Cont button and plot the structure as shown. button and plot the structure as shown.



Thus, it can be seen that the poly oxidation Thus, it can be seen that the poly oxidation step has formed oxide layer on top of the step has formed oxide layer on top of the polysilicon and also on the substrate.polysilicon and also on the substrate.

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After the polysilicon oxidation step, the After the polysilicon oxidation step, the next step is to next step is to dopedope the polysilicon with the polysilicon with phosphorusphosphorus so as to create a so as to create a n+n+ polysilicon polysilicon gategate. .


DopingDopingDopingDopingDopingDopingDopingDoping

Here, the dose of the phosphorus used was Here, the dose of the phosphorus used was 3x103x101313 cmcm--22 with an implant energy of with an implant energy of 20 20 KeVKeV. .

To perform the polysilicon doping step, pull To perform the polysilicon doping step, pull down the down the Commands Commands menu and select menu and select Process Process ⇒⇒⇒⇒⇒⇒⇒⇒ Implant... Implant... to invoke to invoke ATHENA ATHENA ImplantImplant menu as shown.menu as shown.

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After the polysilicon oxidation step, the After the polysilicon oxidation step, the next step is to next step is to dopedope the polysilicon with the polysilicon with phosphorusphosphorus so as to create a so as to create a n+n+ polysilicon polysilicon gategate. .



Here, the dose of the phosphorus used was Here, the dose of the phosphorus used was 3x103x101313 cmcm--22 with an implant energy of with an implant energy of 20 20 KeVKeV. .

To perform the polysilicon doping step, pull To perform the polysilicon doping step, pull down the down the Commands Commands menu and select menu and select Process Process ⇒⇒⇒⇒⇒⇒⇒⇒ Implant... Implant... to invoke to invoke ATHENA ATHENA ImplantImplant menu as shown.menu as shown.

From the From the ImpurityImpurity field, change the field, change the implantation impurity from implantation impurity from ““BoronBoron”” to to ““PhosphorusPhosphorus””..

In the In the DoseDose field, enter a value of field, enter a value of 33 using using and a value of and a value of 1313 in the in the Exp:Exp: field for the field for the exponent.exponent.

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Enter Enter 2020 for the for the EnergyEnergy field, and the field, and the Tilt Tilt field and field and RotationRotation field remain as field remain as 77 and and 30 30 respectively.respectively.



The The Dual PearsonDual Pearson model will still be used model will still be used and the and the Material typeMaterial type remains as remains as CrystallineCrystalline..

Finally, replace the Finally, replace the CommentComment field with field with ““Polysilicon DopingPolysilicon Doping””..

And click on the And click on the WRITEWRITE button. button.

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The following The following implantimplant statements will statements will appear in the text window as shown:appear in the text window as shown:

# Polysilicon Doping# Polysilicon Dopingimplant phosphor dose=3e13 energy=20implant phosphor dose=3e13 energy=20crystalcrystal



Continue the ATHENAContinue the ATHENA simulation using the simulation using the ContCont button and plot the history file as button and plot the history file as shown.shown.

From TONYPLOT, pull down the From TONYPLOT, pull down the PlotPlot menu menu and select and select DisplayDisplay……

The The Display (2D Mesh)Display (2D Mesh) will appears.will appears.

Click on the Click on the ContoursContours icon follows by the icon follows by the ApplyApply button.button.

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The The Net DopingNet Doping of the structure will appear of the structure will appear as shown.as shown.



To view the To view the implanted phosphorusimplanted phosphorus contour contour plot, pull down the plot, pull down the DefineDefine menu and select menu and select ContoursContours……

The The TONYPLOT: ContoursTONYPLOT: Contours menu will menu will appear.appear.

By default, By default, Net DopingNet Doping is being selected. is being selected.

Click the Click the Apply Apply button follows by the button follows by the DismissDismiss button to close the button to close the ContoursContoursmenu.menu.

Pull down the Pull down the Quantity Quantity menu and select menu and select PhosphorusPhosphorus from the list.from the list.

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Click on the Click on the DismissDismiss button again to close button again to close the the Display (2D Mesh) Display (2D Mesh) menu.menu.



The contour plot of the implanted The contour plot of the implanted phosphorus doping profile is as shown. phosphorus doping profile is as shown.

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Next, we will proceed to deposit the spacer Next, we will proceed to deposit the spacer oxide before performing the source and oxide before performing the source and drain implants, drain implants,

Spacer Oxide Spacer Oxide Spacer Oxide Spacer Oxide Spacer Oxide Spacer Oxide Spacer Oxide Spacer Oxide

Deposition Deposition Deposition Deposition Deposition Deposition Deposition Deposition

Here a spacer oxide with a thickness of Here a spacer oxide with a thickness of 0.12 0.12 µµµµµµµµm will be deposited .m will be deposited .

This can be accomplished using the This can be accomplished using the ATHENAATHENA DepositDeposit menu. menu.

Pull down the Pull down the MaterialMaterial menu and select menu and select Oxide Oxide from the list. from the list.

Then, set the material thickness to Then, set the material thickness to 0.120.12..

The The ““Total number of grid layersTotal number of grid layers”” used in used in this case will also be this case will also be 1010. .

Invoke this menu by selecting Invoke this menu by selecting CommandsCommands⇒⇒⇒⇒⇒⇒⇒⇒ ProcessProcess ⇒⇒⇒⇒⇒⇒⇒⇒ Deposit Deposit ⇒⇒⇒⇒⇒⇒⇒⇒ Deposit...Deposit...

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Change the comment to Change the comment to ““Spacer Oxide Spacer Oxide DepositionDeposition”” in the in the CommentComment fieldfield

Spacer Oxide Spacer Oxide Spacer Oxide Spacer Oxide Spacer Oxide Spacer Oxide Spacer Oxide Spacer Oxide

Deposition Deposition Deposition Deposition Deposition Deposition Deposition Deposition

Then, click on the Then, click on the WRITEWRITE button.button.

The deposit statements will appear in the The deposit statements will appear in the DECKBUILDDECKBUILD text window as follows:text window as follows:

# Spacer Oxide Deposition# Spacer Oxide Depositiondeposit oxide thick=0.12 divisions=10deposit oxide thick=0.12 divisions=10

Continue the simulation using the Continue the simulation using the Cont Cont button and plot current structure with button and plot current structure with meshes as shown.meshes as shown.

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To form the sidewall oxide spacer, a dry To form the sidewall oxide spacer, a dry etch step has to be performed. This is done etch step has to be performed. This is done using the using the ATHENA EtchATHENA Etch menu.menu.

Sidewall Spacer Sidewall Spacer Sidewall Spacer Sidewall Spacer Sidewall Spacer Sidewall Spacer Sidewall Spacer Sidewall Spacer

Oxide Formation Oxide Formation Oxide Formation Oxide Formation Oxide Formation Oxide Formation Oxide Formation Oxide Formation

From the From the CommandsCommands menu, select the menu, select the chain chain ProcessProcess ⇒⇒⇒⇒⇒⇒⇒⇒ Etch Etch ⇒⇒⇒⇒⇒⇒⇒⇒ Etch... Etch... andand the the ATHENA Etch menu will appears as shown.ATHENA Etch menu will appears as shown.

From the menu, click on the From the menu, click on the ““Dry Dry thicknessthickness”” for the for the Geometrical typeGeometrical type field. field.

From the From the Material Material field, select field, select Oxide. Oxide.

Enter Enter 0.120.12 for the for the ThicknessThickness field.field.

Add the comment Add the comment ““Spacer Oxide EtchSpacer Oxide Etch”” for for the the CommentComment field.field.


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This will give the following This will give the following EtchEtch statement:statement:

# Spacer Oxide Etch# Spacer Oxide Etchetch oxide dry thick=0.12etch oxide dry thick=0.12

Sidewall Spacer Sidewall Spacer Sidewall Spacer Sidewall Spacer Sidewall Spacer Sidewall Spacer Sidewall Spacer Sidewall Spacer

Oxide Formation Oxide Formation Oxide Formation Oxide Formation Oxide Formation Oxide Formation Oxide Formation Oxide Formation

Continue the Continue the ATHENA ATHENA simulation and plot simulation and plot the etched structure as shown. the etched structure as shown.

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Now, we will perform the source/drain Now, we will perform the source/drain implant to form the n+ source/drain of the implant to form the n+ source/drain of the transistor by implanting arsenic.transistor by implanting arsenic.

Source/Drain Source/Drain Source/Drain Source/Drain Source/Drain Source/Drain Source/Drain Source/Drain

ImplantImplantImplantImplantImplantImplantImplantImplant

In this tutorial, the In this tutorial, the dose of arsenic dose of arsenic used is used is 5 5 x 10x 1015 15 cmcm--33 at an implantation energy of at an implantation energy of 50 50 KeVKeV. .

To perform this implantation step, the To perform this implantation step, the ATHENA ImplantATHENA Implant menu will be used again. menu will be used again.

Invoke the Invoke the Implant menu Implant menu and perform the and perform the following: following:

Change the implantation impurity from Change the implantation impurity from ““PhosphorusPhosphorus”” to to ““ArsenicArsenic”” for the for the ImpurityImpurityfield.field.

In the In the DoseDose field, enter a value of field, enter a value of 55 and a and a value of value of 1515 in the in the Exp:Exp: field. field.

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EnterEnter 5050 for the for the EnergyEnergy field, field, 77 for the for the TiltTiltfield and field and 3030 for the for the RotationRotation field. field.


ImplantImplantImplantImplantImplantImplantImplantImplant

Change the Change the Comment Comment field to field to ““Source/ Source/ Drain ImplantDrain Implant””..

Click on the Click on the WRITEWRITE button and the implant button and the implant statements will appear in the text window as statements will appear in the text window as follows:follows:

# Source/Drain Implant# Source/Drain Implantimplant arsenic dose=5e15 energy=50 implant arsenic dose=5e15 energy=50 crystalcrystal

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The source/drain implant is then followed The source/drain implant is then followed by a short annealing process in by a short annealing process in nitrogen nitrogen for for 1 minutes1 minutes at at 900 900 ooCC and and 1 atmospheric 1 atmospheric pressurepressure. .


AnnealingAnnealingAnnealingAnnealingAnnealingAnnealingAnnealingAnnealing

This annealing process can be carried This annealing process can be carried using the using the DiffuseDiffuse menu as shown.menu as shown.

From the From the Diffuse Diffuse Menu, set the Menu, set the TimeTime to to 1 1 and the and the Temperature Temperature to to 900900. .

From the From the AmbientAmbient field, click on the field, click on the NitrogenNitrogen box.box.

CheckCheck on the on the DiffusionDiffusion model and model and Uncheck Uncheck the the OxidationOxidation model.model.

Change the comment to Change the comment to ““Source/Drain Source/Drain AnnealingAnnealing”” in the in the CommentComment field. field.

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The following diffuse statement will appear The following diffuse statement will appear in the text window:in the text window:

# Source/Drain Annealing# Source/Drain Annealingmethod fermi method fermi diffus time=1 temp=900 nitro press=1.00diffus time=1 temp=900 nitro press=1.00

Continue the simulation and plot theContinue the simulation and plot the Net Net DopingDoping of the structure as shown.of the structure as shown.

Next, we would like to see the change in the Next, we would like to see the change in the Net DopingNet Doping before and after the annealing before and after the annealing process. To do this,process. To do this,

From the From the TONYPLOTTONYPLOT of the of the Source/Drain Source/Drain AnnealedAnnealed structure, pull down the structure, pull down the FileFilemenu, follows by the menu, follows by the Load StructureLoad Structure……

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The The Load StructureLoad Structure menu will appear.menu will appear.



Type in the previous history file generated Type in the previous history file generated during the source/drain implant step (i.e. during the source/drain implant step (i.e. .history12.str.history12.str) in the ) in the FilenameFilename field. field.

Then, pull down the Then, pull down the LoadLoad menu and select menu and select overlayoverlay and then and then DismissDismiss as shown. as shown.

The source/drain implant structure i.e. The source/drain implant structure i.e. ““.history12.str.history12.str”” will then overlay onto the will then overlay onto the annealed structure i.e. annealed structure i.e. ““.history13.str.history13.str”” as as shown. shown.

Notice that the subtitle of the plot indicates Notice that the subtitle of the plot indicates ““Data from multiple filesData from multiple files””..

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After the two structure plots are overlay After the two structure plots are overlay onto each other, perform a onto each other, perform a CutlineCutline by by selecting the selecting the ToolsTools menu in TONYPLOT menu in TONYPLOT follows by follows by Cutline Cutline ……



The The CutlineCutline menu will appear. menu will appear.

Click on the Click on the KeyboardKeyboard icon.icon.

Once done, hit the [Once done, hit the [ReturnReturn] button on ] button on keyboardkeyboard and TONYPLOT will prompt you and TONYPLOT will prompt you for for ConfirmationConfirmation. Click on the . Click on the Confirm Confirm button.button.

And enter the following values for And enter the following values for X X and and YYas shown:as shown:

Start X: 0.1Start X: 0.1 Y: Y: --0.050.05

End X: 0.1End X: 0.1 Y: 0.2 Y: 0.2

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This result in the generation of a oneThis result in the generation of a one--dimensional plot on the right hand side as dimensional plot on the right hand side as shown.shown.



From the 1D plot, it can be seen that the From the 1D plot, it can be seen that the short annealing process has moves the short annealing process has moves the dopants away from the surface of the MOS dopants away from the surface of the MOS structure. structure.

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After forming the source/drain region, the After forming the source/drain region, the next step is to metallize this region.next step is to metallize this region.

Metallization Metallization Metallization Metallization Metallization Metallization Metallization Metallization

In this tutorial, the metallization step is In this tutorial, the metallization step is done by, first forming the contact window done by, first forming the contact window in the source/drain region;in the source/drain region;

To form the contact window in the To form the contact window in the source/drain region, the oxide layer is etch source/drain region, the oxide layer is etch to the left at x = 0.2 to the left at x = 0.2 µµµµµµµµm, using the m, using the ATHENA ATHENA Etch menuEtch menu as follows:as follows:

And next, depositing and patterning the And next, depositing and patterning the Aluminum. Aluminum.

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From the From the Etch Etch menu, click on menu, click on ““LeftLeft”” for the for the Geometrical typeGeometrical type field.field.


Enter Enter 0.20.2 for the for the Etch locationEtch location field. field.

Add the comment Add the comment ““Open Contact WindowOpen Contact Window””for the for the CommentComment field. field.


Continue the Continue the ATHENA ATHENA simulation and plot simulation and plot the etched structure as shown.the etched structure as shown.

The following The following EtchEtch statement will appears statement will appears in the DECKBUILD text window:in the DECKBUILD text window:

# Open Contact Window# Open Contact Windowetch oxide left p1.x=0.2etch oxide left p1.x=0.2

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Next, an aluminum layer of thickness 0.03 Next, an aluminum layer of thickness 0.03 µµµµµµµµm will be deposited onto the structure m will be deposited onto the structure using the using the ATHENA DepositATHENA Deposit menu as menu as follows:follows:


Select Select AluminumAluminum from the from the MaterialMaterial menu, menu, and set its thickness to and set its thickness to 0.030.03. .

For the For the Grid specificationGrid specification parameters, set parameters, set the the ““Total number of grid layersTotal number of grid layers”” to 2. to 2.

Then, click on the Then, click on the WRITEWRITE button. button.

Add a comment Add a comment ““Aluminum DepositionAluminum Deposition”” in in the the CommentComment field.field.

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The following The following DepositDeposit statements will statements will appear in the appear in the DECKBUILDDECKBUILD text window:text window:

# Aluminum Deposition# Aluminum Depositiondeposit aluminum thick=0.03 divisions=2deposit aluminum thick=0.03 divisions=2


Continue the simulation using the Continue the simulation using the Cont Cont button and plot the structure as shown.button and plot the structure as shown.

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Finally, the aluminum layer is etch to the Finally, the aluminum layer is etch to the right starting from right starting from x = 0.18x = 0.18µµµµµµµµmm using the using the EtchEtch menu as follows: menu as follows:


From the From the Etch Etch menu, change the menu, change the Geometrical typeGeometrical type field to field to RightRight..

From the From the MaterialMaterial field, change the field, change the OxideOxidematerial to material to AluminumAluminum. .

Change the comment to Change the comment to ““Etch AluminumEtch Aluminum””for the for the CommentComment field. field.

Enter Enter 0.180.18 for the for the Etch locationEtch location field. field.


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This will give the following statement:This will give the following statement:

# Etch Aluminum# Etch Aluminumetch aluminum right p1.x=0.18etch aluminum right p1.x=0.18


Continue the Continue the ATHENA ATHENA simulation and plot simulation and plot the etched structure as shown.the etched structure as shown.

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In this session, we will extract some of the In this session, we will extract some of the device parameters of the half NMOS device parameters of the half NMOS structure. structure.

Extracting Device Extracting Device Extracting Device Extracting Device Extracting Device Extracting Device Extracting Device Extracting Device

Parameters Parameters Parameters Parameters Parameters Parameters Parameters Parameters

These include the:These include the:

a.a. Junction DepthJunction Depth

b.b. N++ Source/Drain Sheet ResistanceN++ Source/Drain Sheet Resistance

c.c. LDD Sheet Resistance under oxide LDD Sheet Resistance under oxide spacerspacer

d.d. Long Channel Threshold VoltageLong Channel Threshold Voltage

All these can be done by using the All these can be done by using the ExtractExtractmenu in menu in DECKBUILDDECKBUILD. .

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To extract the To extract the Junction DepthJunction Depth: :

Pull down the Pull down the Commands Commands menu and select menu and select the the ExtractExtract…… item.item.

The ATHENA The ATHENA Extract Extract menu will appears.menu will appears.

Type in Type in nxjnxj for the for the Name Name field. field.



Pull down the Pull down the ExtractExtract list and select the list and select the Junction depthJunction depth..

For the For the MaterialMaterial field, the field, the SiliconSilicon material is material is by default selected.by default selected.

On the On the Extract locationExtract location field,field, XX location is location is by default selected. For the by default selected. For the ValueValue field, field, enter enter 0.20.2 and then click on the and then click on the WRITEWRITEbutton.button.

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The The Extract Extract statement will appear in the statement will appear in the text window as follows:text window as follows:

extract name=extract name=““nxjnxj”” xj material=xj material=““SiliconSilicon””mat.occno=1 x.val=0.2 junc.occno=1mat.occno=1 x.val=0.2 junc.occno=1

In this In this ExtractExtract statement:statement:

material="Silicon"material="Silicon" is the material containing is the material containing the junction. In this case, the material is the junction. In this case, the material is SiliconSilicon; ;



name="nxj"name="nxj" is the name for the extracted is the name for the extracted junction depth; junction depth;

mat.occno=1mat.occno=1 instructs the simulator to instructs the simulator to extract the junction depth at the first extract the junction depth at the first occurrence of Silicon layer; occurrence of Silicon layer;

x.val=0.2x.val=0.2 instructs the simulator to extract instructs the simulator to extract the source/drain junction depth at x=0.2the source/drain junction depth at x=0.2µµµµµµµµm;m;

xj xj indicates that junction depth is to be indicates that junction depth is to be extracted;extracted;

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junc.occno=1junc.occno=1 is to extract the junction is to extract the junction depth at first occurrence of the junction. depth at first occurrence of the junction.



For example, an For example, an nn+ source/drain region + source/drain region within a within a pp well on an well on an nn substrate would substrate would have 2 junctions. have 2 junctions.

p Well

n substrate

drainsource

In a more complex structure, there may be In a more complex structure, there may be more than one junction within the same more than one junction within the same material layer. material layer.

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The first junction is between the source The first junction is between the source and and pp well region; while the second well region; while the second junction between the junction between the pp well and well and n n substrate substrate region, region,

p Well

n substrate

drainsource

junction 1

junction 2


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Since the NMOS structure has only one Since the NMOS structure has only one junction. Therefore, the junction junction. Therefore, the junction occurrence number in this case is optional. occurrence number in this case is optional.


p Well

n substrate

drainsource

junction 1

junction 2

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Next, to extract the Next, to extract the N++ Source/Drain Sheet N++ Source/Drain Sheet ResistanceResistance: :

Invoke the Invoke the Extract Extract menu again as shown. menu again as shown.

Then, perform the following: Then, perform the following:

Type in Type in ““n++ sheet resn++ sheet res”” for the for the NameName field.field.



Pull down the Pull down the ExtractExtract list and select the list and select the Sheet resistanceSheet resistance..

For the For the Extract locationExtract location field, with the field, with the X X location selected, enter a value of location selected, enter a value of 0.050.05..

Then, click on theThen, click on the WRITEWRITE button when button when done.done.

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The The ExtractExtract statement will appear in the statement will appear in the text window as follows:text window as follows:

extract name="n++ sheet res" sheet.res extract name="n++ sheet res" sheet.res material="Silicon" mat.occno=1 x.val=0.05 material="Silicon" mat.occno=1 x.val=0.05 region.occno=1region.occno=1

sheet.ressheet.res indicates that sheet resistance is indicates that sheet resistance is to be extracted;to be extracted;



In this statement:In this statement:

mat.occno=1mat.occno=1 and and region.occno=1region.occno=1 specify specify both the material occurrence number and both the material occurrence number and the region occurrence number to be 1; the region occurrence number to be 1;

x.val=0.05x.val=0.05 tell the extract routine where the tell the extract routine where the n++ region is. n++ region is.

This is done by giving the location of a This is done by giving the location of a point within the region at point within the region at x = 0.05 x = 0.05 µµµµµµµµmm. .

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Next, we shall extract the Next, we shall extract the LDD Sheet LDD Sheet ResistanceResistance under the oxide spacer.under the oxide spacer.

Therefore, invoke the Therefore, invoke the Extract Extract menu again to menu again to defined the extract parameters as follows: defined the extract parameters as follows:



Referring to the simulated structure as Referring to the simulated structure as shown, it is reasonable to extract the shown, it is reasonable to extract the LDD LDD Sheet ResistanceSheet Resistance at a point under the oxide at a point under the oxide spacer along spacer along x = 0.3 x = 0.3 µµµµµµµµmm. .

First, enter the First, enter the NameName field as field as ldd sheet resldd sheet res..

Next, change the value of the Next, change the value of the Extract Extract locationlocation field to field to 0.30.3, with the , with the X X location location selected. selected.

X = 0.3 X = 0.3 µµµµµµµµmm

LDD Sheet Resistance LDD Sheet Resistance under oxide spacerunder oxide spacer

Finally, click on the Finally, click on the WRITEWRITE button.button.

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extract name="ldd sheet resextract name="ldd sheet res”” sheet.res sheet.res material="Silicon" mat.occno=1 x.val=0.3 material="Silicon" mat.occno=1 x.val=0.3 region.occno=1region.occno=1

Finally, to extract the Finally, to extract the Long Channel Long Channel Threshold VoltageThreshold Voltage of the NMOS at of the NMOS at x = 0.5 x = 0.5 µµµµµµµµmm::




Change the Change the ExtractExtract field from field from Sheet Sheet ResistanceResistance to to QUICKMOS 1D VtQUICKMOS 1D Vt..

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extract name="ldd sheet resextract name="ldd sheet res”” sheet.res sheet.res material="Silicon" mat.occno=1 x.val=0.3 material="Silicon" mat.occno=1 x.val=0.3 region.occno=1region.occno=1

Finally, to extract the Long Channel Finally, to extract the Long Channel Threshold Voltage of the NMOS at Threshold Voltage of the NMOS at x = 0.5 x = 0.5 µµµµµµµµmm::




Change the Change the ExtractExtract field from field from Sheet Sheet ResistanceResistance to to QUICKMOS 1D VtQUICKMOS 1D Vt..

Click on the Click on the NMOSNMOS for the for the Device typeDevice type field, field,

For the For the NameName field, type in field, type in 1dvt1dvt. .

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Check on the Check on the QssQss field, and enter a value of field, and enter a value of 1e101e10..

On the On the Extract locationExtract location field, enter a value field, enter a value of of 0.50.5..



Click on the Click on the WRITEWRITE button when finished.button when finished.


extract name="1dvt" 1dvt ntype qss=1e10 extract name="1dvt" 1dvt ntype qss=1e10 x.val=0.5x.val=0.5


1dvt1dvt instructs the instructs the Extract Extract routine to routine to extracts the 1D threshold voltage; extracts the 1D threshold voltage;

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ntypentype is the device type. In this case, we is the device type. In this case, we have a nhave a n--type transistor; type transistor;

qss=1e10qss=1e10 is the trapped charge, Qis the trapped charge, Qssss, which , which is given as 1 x 10is given as 1 x 1010 10 cmcm--22



x.val=0.5x.val=0.5 is the point that lies within the is the point that lies within the channel of the device.channel of the device.

Also, note that for Also, note that for 1dvt1dvt extraction, the extraction, the default gate bias is set to default gate bias is set to 00--5 V5 V with the with the substrate at substrate at 0V0V and a default device and a default device temperature of temperature of 300 Kelvin300 Kelvin. .

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Now, we can continue the simulation by Now, we can continue the simulation by clicking on the clicking on the ContCont button.button.

From the output window, it can be seen From the output window, it can be seen that the extracted value for:that the extracted value for:



a. a. Junction Depth Junction Depth is is 0.595944um0.595944um from the from the top of first Silicon layer at x = 0.2top of first Silicon layer at x = 0.2µµµµµµµµm.m.

b. b. N++ Sheet Resistance N++ Sheet Resistance isis 28.6859 28.6859 ΩΩΩΩΩΩΩΩ // at at x = 0.05 x = 0.05 µµµµµµµµm.m.

c. c. LDD Sheet Resistance LDD Sheet Resistance isis 1667.6 1667.6 ΩΩΩΩΩΩΩΩ // at x at x = 0.3= 0.3µµµµµµµµm.m.

d. d. Long Channel Threshold Voltage Long Channel Threshold Voltage isis0.325191V 0.325191V at x = 0.5 at x = 0.5 µµµµµµµµm.m.

And all the extracted values will appears in And all the extracted values will appears in the output window as shown. the output window as shown.

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These extracted information are also These extracted information are also written to the file written to the file ““results.finalresults.final”” in the in the current working directory.current working directory.



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This tutorial has been building one half of a This tutorial has been building one half of a MOSFETMOSFET--like structure. like structure.

It is necessary to obtain the full structure It is necessary to obtain the full structure before exporting the structure to a device before exporting the structure to a device simulator or setting electrode names. simulator or setting electrode names.

Reflecting Half Reflecting Half Reflecting Half Reflecting Half Reflecting Half Reflecting Half Reflecting Half Reflecting Half

NMOS Structure NMOS Structure NMOS Structure NMOS Structure NMOS Structure NMOS Structure NMOS Structure NMOS Structure

To obtain the full structure:To obtain the full structure:

Pull down the Pull down the CommandsCommands menu and select menu and select StructureStructure follows by follows by MirrorMirror. .

The The ATHENA MirrorATHENA Mirror menu will appear.menu will appear.

Click on the Click on the RightRight box for the box for the MirrorMirror field field follows by the follows by the WRITEWRITE button.button.

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And the And the StructureStructure statement is written into statement is written into the text window: the text window:

struct mirror rightstruct mirror right

Reflecting Half Reflecting Half Reflecting Half Reflecting Half Reflecting Half Reflecting Half Reflecting Half Reflecting Half

NMOS Structure NMOS Structure NMOS Structure NMOS Structure NMOS Structure NMOS Structure NMOS Structure NMOS Structure

Continue the simulation and plot the Continue the simulation and plot the resulting full NMOS structure with resulting full NMOS structure with Net Net DopingDoping as shown.as shown.

From this figure, it can be seen that the From this figure, it can be seen that the right half of the structure is a complete right half of the structure is a complete mirror copy of the right part, including mirror copy of the right part, including node coordinates, doping values, etc. node coordinates, doping values, etc.

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To enable biasing in the device simulator To enable biasing in the device simulator ATLASATLAS, it is essential to label the electrodes , it is essential to label the electrodes for the NMOS transistor. for the NMOS transistor.

The electrodes of the structure can be The electrodes of the structure can be defined using the defined using the ATHENAATHENA Electrode Electrode menu. menu.

Specification of Specification of Specification of Specification of Specification of Specification of Specification of Specification of

Electrodes Electrodes Electrodes Electrodes Electrodes Electrodes Electrodes Electrodes

To invoke this menu:To invoke this menu:

Pull down the Pull down the CommandsCommands menu and select menu and select StructureStructure follows byfollows by Electrode...Electrode...

The The ATHENA ElectrodeATHENA Electrode menu will appears. menu will appears.

By default, the By default, the Specified PositionSpecified Position box is box is selected in the selected in the Electrode TypeElectrode Type field. field.

For the For the Name Name field, type in field, type in sourcesource..

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Click on the Click on the XX PositionPosition and set the value to and set the value to 0.10.1 as shown.as shown.




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Click on the Click on the XX PositionPosition and set the value to and set the value to 0.10.1 as shown.as shown.




And the following And the following ElectrodeElectrode statement will statement will appear in the input file: appear in the input file:

electrode name=source x=0.1electrode name=source x=0.1

Simliarly, define the drain electrode using Simliarly, define the drain electrode using ElectrodeElectrode menu as follow:menu as follow:

Here, the Here, the NameName field is change to field is change to drain drain and and the the X PositionX Position is set to is set to 1.11.1..


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The second The second ElectrodeElectrode statement will then statement will then appears in the text window as shown:appears in the text window as shown:

electrode name=drain x=1.1electrode name=drain x=1.1



To define the polysilicon gate electrode, To define the polysilicon gate electrode, use the use the ElectrodeElectrode menu again as shown.menu again as shown.

Change the Change the NameName field to field to gate gate and the and the X X PositionPosition is set to is set to 0.60.6..


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The third The third ElectrodeElectrode statement will then statement will then appears in the text window as shown:appears in the text window as shown:

electrode name=gate x=0.6electrode name=gate x=0.6



In In ATHENAATHENA, a backside electrode can be , a backside electrode can be placed at the bottom of the structure placed at the bottom of the structure without having a metal region there. without having a metal region there.

To specify a backside electrode, click on To specify a backside electrode, click on the the BacksideBackside box from the box from the Electrode TypeElectrode Typeof the of the ATHENA ElectrodeATHENA Electrode menu as shown. menu as shown.

And type in And type in backsidebackside for the for the NameName field.field.


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The final The final ElectrodeElectrode statement will then statement will then appears as shown:appears as shown:

electrode name=backside backsideelectrode name=backside backside



In this statement, the syntax In this statement, the syntax backside backside specify that a flat (zero height) electrode specify that a flat (zero height) electrode will be placed at the bottom of the will be placed at the bottom of the simulation structure. simulation structure.

Continue running the input file and the Continue running the input file and the following notes can be seen from the following notes can be seen from the output window. output window.

With the specification of the electrodes, the With the specification of the electrodes, the NMOS structure is completed.NMOS structure is completed.

The last session will describe on how to The last session will describe on how to save this final structure file. save this final structure file.

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Although, the Although, the DECKBUILD DECKBUILD History functionHistory functionsaves structure files after each process saves structure files after each process step. step.

Saving Saving Saving Saving Saving Saving Saving Saving

Structure File Structure File Structure File Structure File Structure File Structure File Structure File Structure File

However, in many cases it is necessary to However, in many cases it is necessary to save and initialize structures independently. save and initialize structures independently.

To save or load a structure, use the To save or load a structure, use the ATHENA File I/OATHENA File I/O menu by selecting themenu by selecting theCommandsCommands menu follows by menu follows by File I/O...File I/O...

The The File I/OFile I/O menu will appears. menu will appears.

For the For the FormatFormat field, click on the field, click on the Save Save box box and specify and specify nmos.strnmos.str for the for the File nameFile name..

Then, press the Then, press the WRITEWRITE button. button.

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The following line will appears in the input The following line will appears in the input file: file:

struct outfile=nmos.strstruct outfile=nmos.str

Saving Saving Saving Saving Saving Saving Saving Saving

Structure File Structure File Structure File Structure File Structure File Structure File Structure File Structure File

Finally, continue running the input file and Finally, continue running the input file and plot the plot the nmos.strnmos.str structure file as shown. structure file as shown.

NMOS Device Simulation Using ATLASNMOS Device Simulation Using ATLASNMOS Device Simulation Using ATLASNMOS Device Simulation Using ATLASNMOS Device Simulation Using ATLASNMOS Device Simulation Using ATLASNMOS Device Simulation Using ATLASNMOS Device Simulation Using ATLAS

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Getting Started Getting Started Getting Started Getting Started Getting Started Getting Started Getting Started Getting Started

With ATLAS With ATLAS With ATLAS With ATLAS With ATLAS With ATLAS With ATLAS With ATLAS

To start ATLAS under DECKBUILD, type: To start ATLAS under DECKBUILD, type:

deckbuild deckbuild ––as&as&

The The --asas option instructs DECKBUILD to option instructs DECKBUILD to start ATLAS as the default simulator. start ATLAS as the default simulator.

After a short delay, DECKBUILD will appear. After a short delay, DECKBUILD will appear. As can be seen from the DECKBUILD output As can be seen from the DECKBUILD output window, the command prompt is now window, the command prompt is now ATLAS instead of ATHENA. ATLAS instead of ATHENA.

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NMOS Device NMOS Device NMOS Device NMOS Device NMOS Device NMOS Device NMOS Device NMOS Device

SimulationSimulationSimulationSimulationSimulationSimulationSimulationSimulation

In this session, we shall perform the device In this session, we shall perform the device simulation of an NMOS structure. simulation of an NMOS structure.

1.1. Generation of simple Id versus Vgs Generation of simple Id versus Vgs curve with Vds = 0.1V.curve with Vds = 0.1V.

2.2. Extraction of device parameters such Extraction of device parameters such as Vt, Beta and Theta. as Vt, Beta and Theta.

3.3. Generation of Id versus Vds curves Generation of Id versus Vds curves with different Vgswith different Vgs

Here, the following will be demonstrated:Here, the following will be demonstrated:

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Defining Structure Defining Structure Defining Structure Defining Structure Defining Structure Defining Structure Defining Structure Defining Structure

in ATLAS in ATLAS in ATLAS in ATLAS in ATLAS in ATLAS in ATLAS in ATLAS

A device structure can be defined in A device structure can be defined in ThreeThreedifferent waysdifferent ways in ATLAS:in ATLAS:

1.1. An existing structure can be read in An existing structure can be read in from a file. This structure can have been from a file. This structure can have been created by another program such as created by another program such as ATHENA or DEVEDIT. ATHENA or DEVEDIT.

2.2. The input structure can be transferred The input structure can be transferred from ATHENA or DEVEDIT through the from ATHENA or DEVEDIT through the automatic interface feature of DECKBUILD. automatic interface feature of DECKBUILD.

3.3. A structure can be constructed using A structure can be constructed using the ATLAS command language. the ATLAS command language.

The The first first and and second second methods are more methods are more convenient than the convenient than the thirdthird method and are to method and are to be preferred whenever possible. be preferred whenever possible.

In this tutorial, we shall use the In this tutorial, we shall use the first methodfirst methodto read in the NMOS structure that was to read in the NMOS structure that was previously created by ATHENA.previously created by ATHENA.

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Loading NMOS Loading NMOS Loading NMOS Loading NMOS Loading NMOS Loading NMOS Loading NMOS Loading NMOS

Structure Structure Structure Structure Structure Structure Structure Structure

First, we shall define the First, we shall define the MeshMesh statement to statement to loadload--in the NMOS structure that was in the NMOS structure that was previously created by ATHENA. previously created by ATHENA.

To do so:To do so:

Pull down the Pull down the ATLAS CommandsATLAS Commands menu and menu and select select Structure Structure follows by the follows by the MeshMesh…… item. item.

The The ATLAS MeshATLAS Mesh popup window will appear popup window will appear as shown.as shown.

From the From the TypeType field, click on the field, click on the ““Read from Read from filefile”” box. box.

Next, specify the structure file name as Next, specify the structure file name as ““nmos.strnmos.str”” in the in the File nameFile name field. field.

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Loading NMOS Loading NMOS Loading NMOS Loading NMOS Loading NMOS Loading NMOS Loading NMOS Loading NMOS

Structure Structure Structure Structure Structure Structure Structure Structure

Press the Press the WRITEWRITE button to write the button to write the Mesh Mesh statement into DECKBUILD text window as statement into DECKBUILD text window as shown.shown.

go atlasgo atlas##mesh infile=mesh infile=““nmos.strnmos.str””

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Models Command Models Command Models Command Models Command Models Command Models Command Models Command Models Command

GroupGroupGroupGroupGroupGroupGroupGroup

Since the NMOS structure has already been Since the NMOS structure has already been created in ATHENA, we shall skip the created in ATHENA, we shall skip the Structure Specification Command GroupStructure Specification Command Groupand start with the and start with the Models Specification Models Specification Command GroupCommand Group. .

In this command group, we have to specify In this command group, we have to specify the the ModelsModels, , Contact CharacteristicsContact Characteristics and and Interface PropertiesInterface Properties using the using the Model Model statement, statement, Contact Contact statement and statement and Interface Interface statement respectively.statement respectively.

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Specifying the ModelsSpecifying the Models

For simple MOS simulation, the parameters For simple MOS simulation, the parameters SRHSRH and and CVTCVT define the recommended define the recommended models.models.

SRHSRH is the is the Shockley Read HallShockley Read Hall recombination recombination model while the model while the CVTCVT model is the model is the inversion inversion layerlayer model from Lombardi.model from Lombardi.

For detailed information on these models, For detailed information on these models, you can refer to the you can refer to the ATLAS UserATLAS User’’s Manual s Manual Volume IVolume I. .

This This CVTCVT model sets a general purpose model sets a general purpose mobility model including concentration, mobility model including concentration, temperature, parallel field and transverse temperature, parallel field and transverse field dependence. field dependence.

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To define these two models for the NMOS To define these two models for the NMOS structure: structure:

Pull down the Pull down the ATLAS CommandsATLAS Commands menu and menu and select select ModelsModels follows by the follows by the Models Models …… itemitem

The The Deckbuild: ATLAS ModelDeckbuild: ATLAS Model popup will popup will appear as shown. appear as shown.

By default, the By default, the ““MobilityMobility”” model is selected model is selected under the under the CategoryCategory field, field,

Click on the Click on the CVTCVT box under the box under the MOBILITYMOBILITYfield.field.

For the For the Print Model StatusPrint Model Status Field, the Field, the ““YesYes””box is selected by default. This instruct box is selected by default. This instruct ATLASATLAS to print the model status while to print the model status while running in the runtime output.running in the runtime output.

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You can change the default value of the You can change the default value of the CVTCVTmodel by clicking on the model by clicking on the Define ParametersDefine Parametersbutton follows by button follows by CVTCVT……

The The ATLAS Model ATLAS Model –– CVTCVT popup will appears popup will appears as shown.as shown.

Modify the parameters if necessary and Modify the parameters if necessary and then click then click ApplyApply when done.when done.

To add the recombination model: To add the recombination model:

Pull down the Pull down the CategoryCategory menu and select the menu and select the ““RecombinationRecombination”” option. option.

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Three different recombination models will Three different recombination models will then appear as shown.then appear as shown.

Select the Select the SRH (Fixed Lifetimes)SRH (Fixed Lifetimes) model for model for the NMOS structure.the NMOS structure.

Next, click on the Next, click on the WRITEWRITE button and both button and both the the ModelsModels and and Mobility Mobility statements will statements will appear in the DECKBUILD text window as appear in the DECKBUILD text window as shown.shown.

Before proceeding, save the input file by Before proceeding, save the input file by pulling down the pulling down the FileFile menu menu ⇒⇒⇒⇒⇒⇒⇒⇒ Save AsSave As……

TheThe Save AsSave As…… popup window will appear.popup window will appear.

These includes the These includes the Auger Auger model, model, SRH SRH (Fixed Lifetimes) (Fixed Lifetimes) model and model and SRH (Conc. SRH (Conc. Dep. Lifetimes) Dep. Lifetimes) model.model.

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Type in Type in ““nmos_devsim.innmos_devsim.in”” as the as the FileFile name name and click on the and click on the SaveSave button.button.

The input file is now saved.The input file is now saved.

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Specifying Contact Characteristics Specifying Contact Characteristics

An electrode in contact with semiconductor An electrode in contact with semiconductor material is by default assumed to be material is by default assumed to be OhmicOhmic. .

If a work function is defined, the electrode is If a work function is defined, the electrode is treated as a treated as a SchottkySchottky contact. contact.

The The ContactContact statement is used to specify statement is used to specify the metal workfunction of the electrodes. the metal workfunction of the electrodes.

To specify the workfunction of the nTo specify the workfunction of the n--type type polysilicon gate contact using the polysilicon gate contact using the Contact Contact statement:statement:

Pull down the Pull down the CommandsCommands menu and select menu and select Models Models follows by thefollows by the Contacts Contacts …… item.item.

TheThe DECKBUILD: ATLAS Contact DECKBUILD: ATLAS Contact menu will menu will appears.appears.

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Specifying Contact Characteristics Specifying Contact Characteristics

Enter the Enter the Electrode name Electrode name as as ‘‘gategate’’..

Click on the Click on the nn--polypoly box for nbox for n--type type polysilicon. polysilicon.

Then, click on the Then, click on the WRITEWRITE button and the button and the ContactContact statement will appear in the input statement will appear in the input file:file:

contact name=gate n.polycontact name=gate n.poly

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Specifying Interface Properties Specifying Interface Properties

To specify the interface properties of the To specify the interface properties of the NMOS structure, the NMOS structure, the Interface Interface statement is statement is used. used.

This statement is used to define the This statement is used to define the interface charge density and surface interface charge density and surface recombination velocity at interfaces recombination velocity at interfaces between semiconductors and insulators. between semiconductors and insulators.

To defines a fixed charge of To defines a fixed charge of 3 x 103 x 1010 10 cmcm22 at at the interface between silicon and oxide:the interface between silicon and oxide:

Pull down the Pull down the CommandsCommands menu and select menu and select ModelsModels follows byfollows by InterfaceInterface……

The The DECKBUILD: ATLAS InterfaceDECKBUILD: ATLAS Interface menu menu will appear.will appear.

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Specifying Interface Properties Specifying Interface Properties

Enter Enter ‘‘3e103e10’’ for the for the Fixed Charge DensityFixed Charge Densityfield as shown. field as shown.

Click on the Click on the WRITEWRITE button to write the button to write the InterfaceInterface statement into DECKBUILD text statement into DECKBUILD text window:window:

interfaceinterface s.n=0.0 s.p=0.0 qf=3e10s.n=0.0 s.p=0.0 qf=3e10

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Numerical Method Numerical Method Numerical Method Numerical Method Numerical Method Numerical Method Numerical Method Numerical Method

Command GroupCommand GroupCommand GroupCommand GroupCommand GroupCommand GroupCommand GroupCommand Group

Next, we shall select the type of numerical Next, we shall select the type of numerical methods to be used for the simulation. methods to be used for the simulation.

Several different methods can be used for Several different methods can be used for solving the semiconductor device problems. solving the semiconductor device problems.

For the MOS structure, the For the MOS structure, the dede--coupledcoupled(GUMMEL)(GUMMEL), and , and fully coupled (NEWTON)fully coupled (NEWTON)methods are used. methods are used.

In simple terms, the In simple terms, the Gummel Gummel method will method will solve for each unknown in turn keeping the solve for each unknown in turn keeping the other variables constant, repeating the other variables constant, repeating the process until a stable solution is achieved. process until a stable solution is achieved.

On the other hand, the On the other hand, the Newton Newton method, method, solve the total system of unknowns solve the total system of unknowns together. together.

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The The MethodMethod statement can be included by:statement can be included by:

The The Deckbuild: ATLAS MethodDeckbuild: ATLAS Method menu menu appears.appears.

By default, the By default, the NewtonNewton option is selected in option is selected in the the Method fieldMethod field. .

The default setting of the The default setting of the Maximum number Maximum number of iterationsof iterations is is 2525. Change this value if . Change this value if necessary.necessary.

First, pulling down the First, pulling down the CommandsCommands menu menu and selectand select SolutionsSolutions follows byfollows by Method Method ……

Press the Press the WRITEWRITE button when done.button when done.



Select the Select the GummelGummel option as well.option as well.

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The The MethodMethod statement will appears in the statement will appears in the DECKBUILD text window as shown.DECKBUILD text window as shown.

This statement will cause the solver to start This statement will cause the solver to start with with GummelGummel iterations and then switch to iterations and then switch to NewtonNewton, if convergence is not achieved., if convergence is not achieved.



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Solution Solution Solution Solution Solution Solution Solution Solution


In this group, we need to include:In this group, we need to include:

1. The 1. The Log Log statement to save the log files statement to save the log files which contains all the terminal which contains all the terminal characteristics calculated by ATLAS;characteristics calculated by ATLAS;

2. The 2. The SolveSolve statement for solving different statement for solving different bias conditions; and bias conditions; and

3. The 3. The Load Load statement for loading the statement for loading the solution files. solution files.

In this tutorial, the first objective is to obtain In this tutorial, the first objective is to obtain a simple Ia simple Idd versus Vversus Vgsgs curve for the NMOS curve for the NMOS structure. structure.

To achieve this objective, from the To achieve this objective, from the CommandsCommands menu, select menu, select SolutionsSolutions follows follows byby SolveSolve……

The The DECKBUILD: ATLAS TestDECKBUILD: ATLAS Test menu will menu will appear.appear.

Next, click on the the Next, click on the the PropsProps…… button.button.

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And this invoke the And this invoke the Atlas Solve PropertiesAtlas Solve Propertiesmenu. menu.

For the For the Log fileLog file field, change it to field, change it to ““nmos1_nmos1_””as shown.as shown.

Click Click OKOK when done.when done.

Next, right click the mouse anywhere in the Next, right click the mouse anywhere in the Test windowTest window and select and select Add new rowAdd new row..

This add a new row into the worksheet as This add a new row into the worksheet as shown.shown.

Move the mouse over the Move the mouse over the ““gategate”” parameter, parameter, follow by follow by right clickingright clicking on the mouse. A list on the mouse. A list of electrode names will appear. Select of electrode names will appear. Select ““draindrain”” as shown. as shown.

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Then, click on the value under the Then, click on the value under the Initial Initial BiasBias column and change it to column and change it to 0.10.1..

Next, move the mouse within the worksheet Next, move the mouse within the worksheet region again, region again, right clickright click on the mouse and on the mouse and select select ““Add new rowAdd new row”” again.again.

This adds another new row as shown. This adds another new row as shown.

For the For the ““gategate”” row, move the mouse over row, move the mouse over the the CONSTCONST type, right click the mouse and type, right click the mouse and select select ““VAR1VAR1””. .

Click the Click the WRITEWRITE button when done.button when done.

Change the Change the Final BiasFinal Bias value to value to 3.33.3 and and Delta Delta valuevalue to to 0.10.1 as shown.as shown.

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The following statements will then appears The following statements will then appears in in DECKBUILDDECKBUILD text windows:text windows:

solve initsolve initsolve vdrain=0.1solve vdrain=0.1log outf=nmos1_0.loglog outf=nmos1_0.logsolve name=gate vgate=0 vfinal=3.3 solve name=gate vgate=0 vfinal=3.3 vstep=0.1vstep=0.1

a. The statements as shown above start a. The statements as shown above start with the with the ““solve initsolve init”” statement. statement.

b. The second b. The second SolveSolve statement i.e. statement i.e. ““solve solve vdrain=0.1vdrain=0.1”” will perform a dc bias of will perform a dc bias of 0.1V0.1V at at the drain electrode. the drain electrode.

This statement provides an initial guess for This statement provides an initial guess for the potential and carrier concentrations at the potential and carrier concentrations at the zero bias (or thermal equilibrium) case. the zero bias (or thermal equilibrium) case.

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The following statements will then appears The following statements will then appears in in DECKBUILDDECKBUILD text windows:text windows:

solve initsolve initsolve vdrain=0.1solve vdrain=0.1log outf=nmos1_0.loglog outf=nmos1_0.logsolve name=gate vgate=0 vfinal=3.3 solve name=gate vgate=0 vfinal=3.3 vstep=0.1vstep=0.1

c. The c. The LogLog statement is use to save all the statement is use to save all the simulation results calculated by ATLAS in simulation results calculated by ATLAS in the the nmos1_0.lognmos1_0.log file. file.

d. Finally, the last d. Finally, the last SolveSolve statement will ramp statement will ramp the the gategate voltage from voltage from 0V0V to to 3V3V with a bias with a bias step sizestep size of of 0.1V0.1V

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Extracting Device Parameters Extracting Device Parameters

In this workshop, the second objective is to In this workshop, the second objective is to obtain some of the device parameters such obtain some of the device parameters such as as VtVt, , Beta Beta and and ThetaTheta. To do this:. To do this:

Pull down the ATLAS Pull down the ATLAS CommandsCommands menu and menu and select select ExtractExtract follows byfollows by DeviceDevice……

The The ATLAS ExtractionATLAS Extraction menu appear as menu appear as shown.shown.

By default, By default, VtVt is being select in the is being select in the Test Test namename field. field.


Also, user can modify the default extract Also, user can modify the default extract expression if necessary.expression if necessary.

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The The Vt ExtractVt Extract statement will then appears statement will then appears in in DECKBUILDDECKBUILD text windows as shown:text windows as shown:

extract name="vt"(xintercept(maxslope extract name="vt"(xintercept(maxslope (curve(abs(v."gate") , abs(i."drain")))) (curve(abs(v."gate") , abs(i."drain")))) --abs(ave(v."drain"))/2.0)abs(ave(v."drain"))/2.0)

Next, invoke the Next, invoke the Deckbuild: ATLAS Deckbuild: ATLAS ExtractionExtraction menu again. menu again.

Then, click on the Then, click on the Test nameTest name field and field and change it to change it to Beta Beta as shown.as shown.


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The The Beta ExtractBeta Extract statement will then statement will then appears in appears in DECKBUILDDECKBUILD text windows as text windows as shown:shown:

extractname="beta"slope(maxslope(curve extractname="beta"slope(maxslope(curve (abs(v."gate"),abs(i."drain"))))*(1.0/abs(ave((abs(v."gate"),abs(i."drain"))))*(1.0/abs(ave(v."drain")))v."drain")))

Finally, invoke the Finally, invoke the ExtractionExtraction menu again menu again and change the and change the Test nameTest name field to field to Theta Theta as as shown.shown.

Click on the Click on the WRITEWRITE button and the button and the Theta Theta ExtractExtract statement will then appears:statement will then appears:

extract name="theta" ((max(abs(v."drain"))* extract name="theta" ((max(abs(v."drain"))* $"beta")/max(abs(i."drain")))$"beta")/max(abs(i."drain")))--(1.0(max(abs (1.0(max(abs (v."gate")) (v."gate")) -- ($"vt")))($"vt")))

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Before running the simulation, we need to Before running the simulation, we need to use the use the TonyplotTonyplot statement to plot the statement to plot the simulation results. simulation results.

To automatically plot the ITo automatically plot the Idd versus Vversus Vgsgs, , simply type: simply type:

tonyplot nmos1_0.logtonyplot nmos1_0.log

After the After the last Extractlast Extract statement.statement.

Now, we can start running the simulation. Now, we can start running the simulation.

Once the simulation is completed, Once the simulation is completed, TONYPLOTTONYPLOT will automatically be invoked will automatically be invoked with the Iwith the Idd versus Vversus Vgsgs characteristics as characteristics as shown.shown.

Press the Press the run run button to start the device button to start the device simulator.simulator.

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Also, the extracted device parameters i.e. Also, the extracted device parameters i.e. VtVt, , BetaBeta and and ThetaTheta can be seen from the can be seen from the runtime output as shown.runtime output as shown.

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Generating Families of CurvesGenerating Families of Curves

The final objective of this tutorial is to The final objective of this tutorial is to generate families of Igenerate families of Idd versus Vversus Vdsds curves curves with different Vwith different Vgsgs

In order to stop the previous In order to stop the previous ““nmos1_0.lognmos1_0.log””from saving the later terminal from saving the later terminal characteristics, we need to add another Log characteristics, we need to add another Log statement as follows:statement as follows:

log offlog off

Then, invoke the Then, invoke the TestTest menu to define the menu to define the gate bias by pulling down the gate bias by pulling down the CommandsCommandsmenu and select menu and select SolutionsSolutions follows by follows by SolveSolve……

Click on the Click on the PropProp…… button and change the button and change the Write modeWrite mode field to field to ““LineLine””. Click . Click OKOK when when done.done.

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Double click on the Double click on the ““gategate”” row, then right row, then right the mouse and select the mouse and select Delete marked rowDelete marked row..

Next, mouse the mouse over Next, mouse the mouse over ““draindrain””, right , right click the mouse and select click the mouse and select ““gategate”” from the from the list.list.

Then, change the Then, change the initial biasinitial bias of gate to of gate to 1.11.1

Click on the Click on the WRITE WRITE button and the button and the SolveSolvestatement will appears:statement will appears:

solve vgate=1.1 solve vgate=1.1

In order to save the output from this In order to save the output from this solution in a solution file,solution in a solution file,

Type the Type the ““outf=solve1outf=solve1”” option in the option in the SolveSolvestatement as shown: statement as shown:

solve vgate=1.1 outfile=solve1solve vgate=1.1 outfile=solve1

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Duplicate the Duplicate the Solve Solve statement statement ““solve solve vgate=1.1 outfile=solve1vgate=1.1 outfile=solve1”” for 2 times as for 2 times as shown.shown.

Then, change the vgate to Then, change the vgate to 2.22.2 and and 3.33.3 while while the outfile to the outfile to solve2 solve2 and and solve3solve3 as follows:as follows:

solve vgate=2.2 outfile=solve2solve vgate=2.2 outfile=solve2solve vgate=3.3 outfile=solve3solve vgate=3.3 outfile=solve3

Next, we will use the Next, we will use the ATLAS TestATLAS Test menu menu again to set the again to set the SolveSolve statement for ramping statement for ramping the drain voltage from 0 V to 3.3 V. the drain voltage from 0 V to 3.3 V.

Select Select CommandsCommands ⇒⇒⇒⇒⇒⇒⇒⇒ SolutionsSolutions ⇒⇒⇒⇒⇒⇒⇒⇒ SolveSolve……to invoke to invoke ATLAS TestATLAS Test menu.menu.

Click on the Click on the PropProp…… button and change the button and change the Write modeWrite mode to to ““TestTest”” and and Log fileLog file to to ““nmos2_nmos2_””. Click . Click OKOK when done.when done.

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In the worksheet area, change the In the worksheet area, change the NameNamefrom from ““gategate”” to to ““draindrain””, the , the TypeType from from ““CONSTCONST”” to to ““VAR1VAR1””, the , the ““Initial BiasInitial Bias”” to to 00, , ““Final BiasFinal Bias”” to to 3.33.3 and and ““DeltaDelta”” to to 0.30.3. .


Next, we will load in the solution file i.e. Next, we will load in the solution file i.e. ““solve1solve1”” of the gate bias at 1.1V using the of the gate bias at 1.1V using the LoadLoad menu and replace it with the menu and replace it with the ““solve solve initinit”” statement. To do so,statement. To do so,

The following statements are as shown The following statements are as shown below:below:

solve initsolve initlog outfile=nmos2_0.loglog outfile=nmos2_0.logsolve name=drain vdrain=0 vfinal=3.3solve name=drain vdrain=0 vfinal=3.3vstep=0.3vstep=0.3

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First, highlight the First, highlight the ““solve initsolve init”” statement.statement.

From the From the Commands Commands menu, select menu, select SolutionsSolutions ⇒⇒⇒⇒⇒⇒⇒⇒ LoadLoad……

This invoke the This invoke the ATLAS LoadATLAS Load menu.menu.

Type in Type in ““solve1solve1”” for the for the File nameFile name. Click on . Click on Format Format field and select the field and select the SPISCESSPISCES format. format. Then, press the Then, press the WRITEWRITE button. button.

A prompt will appears as shown. Click on A prompt will appears as shown. Click on ““Yes, replace selectionYes, replace selection”” button.button.

The The ““load infile=nmos2_0.logload infile=nmos2_0.log”” statement statement will then replace the will then replace the ““solve initsolve init”” as shown. as shown.

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Therefore, the following Therefore, the following LoadLoad, , LogLog and and Solve Solve statements:statements:

load infile=solve1load infile=solve1log outfile nmos2_0.loglog outfile nmos2_0.logsolve name=drain vdrain=0 vfinal=3.3 solve name=drain vdrain=0 vfinal=3.3 vstep=0.3 vstep=0.3

will solve the Iwill solve the Idd versus Vversus Vdsds for Vfor Vgsgs = 1.1V and = 1.1V and save the results in the save the results in the ““nmos2_0.lognmos2_0.log”” file. file.

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To solve the ITo solve the Idd versus Vversus Vdsds for Vfor Vgsgs = 2.2V and = 2.2V and 3.3V:3.3V:

Simply duplicate the Simply duplicate the LoadLoad, , LogLog and and SolveSolvestatements for 2 times. statements for 2 times.

Then, change the Then, change the input fileinput file name from name from ““solve1solve1”” to to ““solve2solve2”” and and ““solve3solve3””..

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Also, change the Also, change the log file namelog file name to to ““nmos3_0.lognmos3_0.log”” and and ““nmos4_0.lognmos4_0.log”” as as shown:shown:

load infile=solve2load infile=solve2log outfile nmos3_0.loglog outfile nmos3_0.logsolve name=drain vdrain=0 vfinal=3.3 solve name=drain vdrain=0 vfinal=3.3 vstep=0.3vstep=0.3

load infile=solve3load infile=solve3log outfile nmos4_0.loglog outfile nmos4_0.logsolve name=drain vdrain=0 vfinal=3.3 solve name=drain vdrain=0 vfinal=3.3 vstep=0.3vstep=0.3

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To plot all the 3 log files results in a single To plot all the 3 log files results in a single plot, type the following plot, type the following Tonyplot Tonyplot statement: statement:

tonyplot tonyplot ––overlay nmos2_0.log nmos3_0.log overlay nmos2_0.log nmos3_0.log nmos4_0.log nmos4_0.log --set nmos.setset nmos.set

Finally, type the statement: Finally, type the statement:

quit quit

to quit from the simulation to quit from the simulation

b. The b. The ––setset option is used to load the set file option is used to load the set file and restore the display to the condition that and restore the display to the condition that TONYPLOT was in when that set file was TONYPLOT was in when that set file was created.created.

a. The a. The ––overlayoverlay option is to overlay all the 3 option is to overlay all the 3 log files in a single plot;log files in a single plot;

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Once the simulation is completed, Once the simulation is completed, TONYPLOT will automatically be invoked TONYPLOT will automatically be invoked with the families of Iwith the families of Idd versus Vversus Vdsds

characteristics as shown. characteristics as shown.

We can now continue running the We can now continue running the simulation by pressing the simulation by pressing the Cont Cont button on button on the Deckbuild control. the Deckbuild control.

Date post:	26-Dec-2015
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