© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 1
Rochester Institute of Technology
Microelectronic Engineering
ROCHESTER INSTITUTE OF TECHNOLOGYMICROELECTRONIC ENGINEERING
Surface MEMS Fabrication Details
Dr. Lynn Fuller, Adam Wardas, Casey Gonta, Patsy Cadareanu
Webpage: http://people.rit.edu/lffeeeMicroelectronic Engineering
Rochester Institute of Technology82 Lomb Memorial DriveRochester, NY 14623-5604
Email: [email protected] webpage: http://www.rit.edu/kgcoe/microelectronic
11-1-2017 SurfaceMEMsFabricationDetails2017.ppt
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 2
Rochester Institute of Technology
Microelectronic Engineering
OUTLINE
IntroductionDevice Cross SectionMaskmakingStepper JobsFabrication DetailsSignal ProcessingPackaging TestingSummaryReferencesHomework
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 3
Rochester Institute of Technology
Microelectronic Engineering
INTRODUCTION
This document provides detailed information on RIT’s surface micromachine process. This process is capable of making many different types of MEMS devices. This MEMS fabrication process is CMOS compatible (with some modifications) back end module that can be added to realize compact microsystems (CMOS plus MEMS). This version is a simplified 4 or 5 photo level process to take advantage of 4 levels per plate maskmaking and to minimize the time to fabricate the devices.
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 4
Rochester Institute of Technology
Microelectronic Engineering
GENERIC DEVICE CROSS SECTION
Starting Wafer
FieldOxide
Bottom Poly
Metal Layer
Bottom Poly 1 (Red) Layer 1Sacrificial Oxide (Blue Outline) Layer 2Contact Cut (White) Layer 6Metal (Blue) Layer 7Outline (Yellow Outline) Layer 9
Sacrificial Layer
Outline is only for layout, drawing a 4.5mm by 4.5mm outline, the maximum area for individual device designs .
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 5
Rochester Institute of Technology
Microelectronic Engineering
MEMS MULTICHIP PROJECT TEMPLATE
4.5mm by 4.5mmdesign spacefor each project
4 different projects
Total 10 mm by 10 mm including 1 mm for sawing into 4 chips. Wafer sawing is easier if all chips are the same size
10
mm
5 mm
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 6
Rochester Institute of Technology
Microelectronic Engineering
MEMS MULTICHIP PROJECT TEMPLATE
4.5mm by 4.5mmdesign spacefor each project
4 different projects
Total 10 mm by 10 mm including 1 mm for sawing into 4 chips. Wafer sawing is easier if all chips are the same size
10
mm
5 mm
Your
Design
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 7
Rochester Institute of Technology
Microelectronic Engineering
2017 MULTICHIP PROJECT FINAL LAYOUT
10
mm
Total 10 mm by 10 mm including 1 mm for sawing into 4 4.5mm by 4.5 mm chips.
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 8
Rochester Institute of Technology
Microelectronic Engineering
MASK ORDER FORM
x
MEMS-2017-Final.gds 410mm x 10mmDr Fuller
RIT
X yes, 4 levels per plate
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 9
Rochester Institute of Technology
Microelectronic Engineering
MASK ORDER FORM DETAILS
Reticle
Number
Reticle
Name
Design
Layer .gds
#’s
Boolean Function Dark/
Clear
Comment
1 Poly1 1 None Clear Mirror
2 Cut 6 6 Inverted Dark Mirror
3 SacOx 2 None Clear Mirror
4 Metal 7 None Clear Mirror
Design Layer 9 Out (outline) is not used. It is only for placement of projects on the multi-project reticle template.
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 10
Rochester Institute of Technology
Microelectronic Engineering
SURFACE MEMS 2017 FABRICATION PROCESS
16. ET29 – Etch Oxide 17. ET07 - Resist Strip, Recipe FF18. CL01 – RCA Clean19. PH03 – level 3 Sac Layer Define20. ETXX –HF Dip21. ME01 – Metal Deposition - Al22. PH03 – level 4 Metal -2um23. ET55 – Metal Etch – wet etch24. SAW1– Saw wafers ½ way through24. ET07 – Resist Strip and Release, wet?25. TE01 – wafer level testing26. Packaging and Testing27. SEM1 – Pictures and videos
11-1-17
1. Starting wafer2. PH03 – level 0, Marks3. ET29 – Zero Etch4. ID01-Scribe Wafer ID, D1…5. ET07 – Resist Strip, Recipe FF6. CL01 – RCA clean7. OX04 – 6500Å Oxide Tube 18. CV01 – LPCVD Poly 5000Å9. IM01 – Implant P31, 2E16, 100KeV10. PH03 – level 1 Poly11. ET08 – Poly Etch12. ET07 – Resist Strip, Recipe FF13. CL01- RCA Clean 14. OX05 – 700Å Dry Oxide15. PH03 – level 2 Contact Cut
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 11
Rochester Institute of Technology
Microelectronic Engineering
STARTING WAFER – SCRIBE ID01
Starting Wafer
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 12
Rochester Institute of Technology
Microelectronic Engineering
SSI COAT AND DEVELOP TRACK FOR 6” WAFERS
Use Recipe: COAT.rcp and DEVELOP.rcp
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 13
Rochester Institute of Technology
Microelectronic Engineering
RECIPES FOR RESIST COAT AND DEVELOP
Level Level
Name
Resist Coat Recipe Develop
Recipe
Resist
Thickness
0 Zero OIR-620 Coat Develop 1.0um
1 Poly 1 OIR-620 Coat Develop 1.0um
2 CC OIR-620 Coat Develop 1.0um
3 Sac Layer S1827 MEMSCOAT1 MEMSDEV1 3.0um
4 Metal 1 S1827 MEMSCOAT2 Hand Develop 4.5um
MEMSCOAT2.rcp no HMDS, 2500rpm, 30sec, Hand Dispense, 110°C, 1min, Exposure for S1827, 525mj/cm2, Focus +2.0, NA=0.48, s=0.45, Hand Develop, no hardbake, no HMDS,
MEMSCOAT1.rcp 4000rpm, 30sec, Hand Dispense, 110°C, 1min Exposure for S1827, 525mj/cm2, Focus +2.0, NA=0.48, s=0.45MEMSDEV.rcp has 200 second develop time, hardbake 140°C
SacrificialLayer
Metal
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 14
Rochester Institute of Technology
Microelectronic Engineering
PHOTORESIST PROCESSING
SPIN COAT
OIR 620-10
Resist
3250rpm, 30 sec.
SOFT BAKE
90 °C
60 sec.
DEHYDRATE BAKE/
HMDS PRIMING
HMDS Vapor
Prime
140 °C, 60 sec.
DEVELOP.RCP
POST EXPOSURE BAKE
110 °C, 60 sec.
HARD BAKE
120 °C, 60 sec.
COAT.RCP
DEVELOP
DI Wet
CD-26 Developer
48sec. Puddle,
30sec. Rinse,
30sec., 3750rpm
Spin Dry
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 15
Rochester Institute of Technology
Microelectronic Engineering
ASML 5500/200
NA = 0.48 to 0.60 variables= 0.35 to 0.85 variable
With Variable Kohler, orVariable Annular illuminationResolution = K1 l/NA
= ~ 0.35µm for NA=0.6, s =0.85
Depth of Focus = k2 l/(NA)2
= 1.0 µm for NA = 0.6i-Line Stepper l = 365 nm
22 x 27 mm Field Size
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 16
Rochester Institute of Technology
Microelectronic Engineering
STEPPER JOB
Mask Barcode:
Stepper Jobname: MCEE770-MEMS4XLevel 0 (combi reticle)Level Clearout (combi reticle)
Level Poly 1Level CCLevel SacOxLevel Metal
Level MEMS-Test (no alignment)
After photo prior to etch inspect the alignment marks.
They have to be perfect. If not rework the photo step.
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 17
Rochester Institute of Technology
Microelectronic Engineering
DRYTEK QUAD RIE TOOL
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 18
Rochester Institute of Technology
Microelectronic Engineering
ZERO ETCH FOR ASML ALIGNMENT MARKS
Recipe Name: ZEROETCHChamber 3Power 200WPressure 100 mTorrGas 1 CHF3 50 sccmGas 2 CF4 25 sccmGas 3 Ar 0 sccmGas 4 O2 10 sccm
Max Time = 120 seconds
Silicon Etch Rate 650 Å/min 8.8 um L/S 8 um L/S
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 19
Rochester Institute of Technology
Microelectronic Engineering
SCRIBE WAFER WITH ID NUMBER
Wafer has alignment marks etched in two locations.
Scribe on back of wafer
near the wafer flat
ID numbers D1, D2…etc.
D1
FrontBack
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 20
Rochester Institute of Technology
Microelectronic Engineering
ASHER, SCRIBE, RCA CLEAN & SRD
Gassonics Asher
Recipe FF
RCA Clean Bench
O2 + Energy = 2 OO is reactive and will combinewith plastics, wood, carbon,
photoresist, etc.
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 21
Rochester Institute of Technology
Microelectronic Engineering
RCA CLEAN
DI waterrinse, 5 min.
H20 - 50HF - 130 sec.
HPMHCL - 1part
H2O2 - 1partsH2O - 17parts70 °C, 15 min.
SPIN/RINSEDRY
APMNH4OH - 1partH2O2 - 1partsH2O - 17parts70 °C, 15 min.
DI waterrinse, 5 min.
DI waterrinse, 5 min.
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 22
Rochester Institute of Technology
Microelectronic Engineering
USING EXCEL SPREADSHEET FOR OXIDE GROWTH CALCULATIONS
These spreadsheets are available on Dr. Fullers webpage.
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 23
Rochester Institute of Technology
Microelectronic Engineering
BRUCE FURNACE RECIPE 406 – WET OXIDE 6,500Å
1100°C
800 °C
Boat Out Boat In Boat Out
Load Push Stabilize Ramp-Up Soak Anneal Ramp-Down Pull
Recipe #406
800 °C
25 °C
Any
0 lpm
none
800 °C
At the end of a run the furnace returns to Interval 0 which is set for boat out, 25 °C and no gas flow. The furnace waits in that state until someone aborts the current recipe or loads a new recipe.
Wet Oxide Growth, Target 6,500 Å, Tube 1
Interval 0 Interval 1 Interval 2 Interval 3 Interval 4 Interval 5 Interval 6 Interval 7 Interval 8
12 min 15 min 30 min 5 min 65 min 5 min 60 min 12 min
10 lpm 10 lpm 5 lpm 5 lpm 3.6/2 lpm 15 lpm 10 lpm 15 lpm
N2 N2 N2 O2 O2/H2 N2 N2 N2
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 24
Rochester Institute of Technology
Microelectronic Engineering
BRUCE FURNACE
Tube 1 Steam Oxides
Tube 2 P-type Diffusion
Tube 3 N-type Diffusion
Tube 4 Dry Oxides and
Gate Oxides
Tube 1
Tube 2
Tube 3
Tube 4
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 25
Rochester Institute of Technology
Microelectronic Engineering
TENCORE FT-300 SPECROMAP
Record:
Mean
Std Deviation
Min
Max
No of Points
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 26
Rochester Institute of Technology
Microelectronic Engineering
AFTER 6500Å OXIDE GROWTH
Starting Wafer
6500 Å
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 27
Rochester Institute of Technology
Microelectronic Engineering
DEPOSIT POLYSILICON
Poly Target 5000ALPCVD, 610C, Rate ~64Å/minTime~78 minDo not use log sheet for rate/time
Recipe POLY 610Temp = 610°CPressure = 300 mTorrSilane Flow = 100 sccm
Substrate
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 28
Rochester Institute of Technology
Microelectronic Engineering
POLYSILICON DOPING
Ion Implant P31Dose = 2E16 cm-2Energy = 100KeVTime ~20min at 400 µA
Substrate
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 29
Rochester Institute of Technology
Microelectronic Engineering
SSI COAT AND DEVELOP TRACK FOR 6” WAFERS
Use Recipe: Coat.rcp and Develop.rcp
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 30
Rochester Institute of Technology
Microelectronic Engineering
RECIPES FOR RESIST COAT AND DEVELOP
Level Level
Name
Resist Coat Recipe Develop
Recipe
Resist
Thickness
0 Zero OIR-620 Coat Develop 1.0um
1 Poly 1 OIR-620 Coat Develop 1.0um
2 CC OIR-620 Coat Develop 1.0um
3 Sac Layer S1827 MEMSCOAT1 MEMSDEV1 3.0um
4 Metal 1 S1827 MEMSCOAT2 Hand Develop 4.5um
MEMSCOAT2.rcp no HMDS, 2500rpm, 30sec, Hand Dispense, 110°C, 1min, Exposure for S1827, 525mj/cm2, Focus +2.0, NA=0.48, s=0.45, Hand Develop, no hardbake, no HMDS,
MEMSCOAT1.rcp 4000rpm, 30sec, Hand Dispense, 110°C, 1min Exposure for S1827, 525mj/cm2, Focus +2.0, NA=0.48, s=0.45MEMSDEV.rcp has 200 second develop time, hardbake 140°C
SacrificialLayer
Metal
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 31
Rochester Institute of Technology
Microelectronic Engineering
ASML 5500/200
NA = 0.48 to 0.60 variables= 0.35 to 0.85 variable
With Variable Kohler, orVariable Annular illuminationResolution = K1 l/NA
= ~ 0.35µm for NA=0.6, s =0.85
Depth of Focus = k2 l/(NA)2
= 1.0 µm for NA = 0.6i-Line Stepper l = 365 nm
22 x 27 mm Field Size
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 32
Rochester Institute of Technology
Microelectronic Engineering
STEPPER JOB
Mask Barcode:
Stepper Jobname: MCEE770-MEMS4XLevel 0 (combi reticle)Level Clearout (combi reticle)
Level Poly 1Level CCLevel SacOxLevel Metal
Level MEMS-Test (no alignment)
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 33
Rochester Institute of Technology
Microelectronic Engineering
AFTER PHOTORESIST COAT, EXPOSE & DEVELOP
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
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Rochester Institute of Technology
Microelectronic Engineering
AFTER POLY1 ETCH
Drytek Quad
Recipe FACPOLY
Etch Rate ~1150Å/min
5000Å Poly
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 35
Rochester Institute of Technology
Microelectronic Engineering
2 OF 4 CHAMBERS IN THE DRYTEK QUAD RIE TOOL
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 36
Rochester Institute of Technology
Microelectronic Engineering
PLASMA ETCHING IN THE DRYTEK QUAD
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 37
Rochester Institute of Technology
Microelectronic Engineering
ANISOTROPIC POLY GATE ETCH RECIPE
Anisotropic Poly Gate Etch Recipe
SF6 30 sccm, CHF3 30 sccm, O2 5 sccm, RF Power 160 w, Pressure 40 mTorr,
1900 A/min (Anisotropic), Resist Etch Rate 300 A/min, Oxide Etch Rate 200 A/min
Recipe Name: FACPOLY Step 2Chamber 2Power 160 wattsPressure 40 mTorrGas SF6Flow 30 sccmGas CHF3Flow 30 sccmGas O2Flow 5 sccmPoly Etch Rate 1150 Å/minPhotoresist Etch Rate: 300 Å/minOxide Etch Rate: 200 Å/min
Endpoint See Video
https://people.rit.edu/lffeee/Videos.htm
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
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Rochester Institute of Technology
Microelectronic Engineering
STRIP RESIST, RCA CLEAN
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 39
Rochester Institute of Technology
Microelectronic Engineering
GROW 700Å DRY OXIDE
This oxide is to insulate the poly
so that metal can cross poly and
not make connection.
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 40
Rochester Institute of Technology
Microelectronic Engineering
BRUCE FURNACE RECIPE 270 – 700Å DRY OXIDE
1000°C
800 °C
Boat Out Boat In Boat Out
Load Push Stabilize Ramp-Up Soak Anneal Ramp-Down Pull
12 min 15 min 20 min 93 min 5 min 40 min 15 min
10 lpm 10 lmp 5 lpm 10 lpm 15 lpm 10 lpm 5 lpm
N2 N2 O2 O2/ N2 N2 N2
Recipe #270
Interval 0 Interval 1 Interval 2 Interval 3 Interval 4 Interval 5 Interval 6 Interval 7
800 °C
25 °C
Any
0 lpm
none
800 °C
At the end of a run the furnace returns to Interval 0 which is set for boat out, 25 °C and no gas flow. The furnace waits in that state until someone aborts the current recipe or loads a new recipe.
Dry Oxide Growth, Target 700 Å
Verified: 3-1-04
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 41
Rochester Institute of Technology
Microelectronic Engineering
RECIPES FOR RESIST COAT AND DEVELOP
Level Level
Name
Resist Coat Recipe Develop
Recipe
Resist
Thickness
0 Zero OIR-620 Coat Develop 1.0um
1 Poly 1 OIR-620 Coat Develop 1.0um
2 CC OIR-620 Coat Develop 1.0um
3 Sac Layer S1827 MEMSCOAT1 MEMSDEV1 3.0um
4 Metal 1 S1827 MEMSCOAT2 Hand Develop 4.5um
MEMSCOAT2.rcp no HMDS, 2500rpm, 30sec, Hand Dispense, 110°C, 1min, Exposure for S1827, 525mj/cm2, Focus +2.0, NA=0.48, s=0.45, Hand Develop, no hardbake, no HMDS,
MEMSCOAT1.rcp 4000rpm, 30sec, Hand Dispense, 110°C, 1min Exposure for S1827, 525mj/cm2, Focus +2.0, NA=0.48, s=0.45MEMSDEV.rcp has 200 second develop time, hardbake 140°C
SacrificialLayer
Metal
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 42
Rochester Institute of Technology
Microelectronic Engineering
AFTER CUT PHOTO AND BOE ETCH
Substrate
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 43
Rochester Institute of Technology
Microelectronic Engineering
TEST STRUCTURES
Lithographic overlay and resolution test structure
Electrical Tests:ResistanceSheet ResistanceContact Resistance
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 44
Rochester Institute of Technology
Microelectronic Engineering
RESIST STRIP
Substrate
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 45
Rochester Institute of Technology
Microelectronic Engineering
STEPPER JOB
Mask Barcode:
Stepper Jobname: MCEE770-MEMS4XLevel 0 (combi reticle)Level Clearout (combi reticle)
Level Poly 1Level CCLevel Sac Layer Level Metal
Level MEMS-Test (no alignment)
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 46
Rochester Institute of Technology
Microelectronic Engineering
RECIPES FOR RESIST COAT AND DEVELOP
Level Level
Name
Resist Coat Recipe Develop
Recipe
Resist
Thickness
0 Zero OIR-620 Coat Develop 1.0um
1 Poly 1 OIR-620 Coat Develop 1.0um
2 CC OIR-620 Coat Develop 1.0um
3 Sac Layer S1827 MEMSCOAT1 MEMSDEV1 3.0um
4 Metal 1 S1827 MEMSCOAT2 Hand Develop 4.5um
MEMSCOAT2.rcp no HMDS, 2500rpm, 30sec, Hand Dispense, 110°C, 1min, Exposure for S1827, 525mj/cm2, Focus +2.0, NA=0.48, s=0.45, Hand Develop, no hardbake, no HMDS,
MEMSCOAT1.rcp 4000rpm, 30sec, Hand Dispense, 110°C, 1min Exposure for S1827, 525mj/cm2, Focus +2.0, NA=0.48, s=0.45Then Flood expose wafer edge using black transparency mask thenMEMSDEV.rcp, 200 second develop time, hardbake 140°C
SacrificialLayer
Metal
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 47
Rochester Institute of Technology
Microelectronic Engineering
BLACK PLASTIC MASK – FLOOD EXPOSE WAFER EDGE
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
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Rochester Institute of Technology
Microelectronic Engineering
AFTER SAC LAYER PHOTO AND DEVELOP
Substrate
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 49
Rochester Institute of Technology
Microelectronic Engineering
PRE METAL HF DIP
SPIN/RINSEDRY
H20 - 50HF - 130 sec.
DI waterrinse, 5 min.
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 50
Rochester Institute of Technology
Microelectronic Engineering
SPUTTER ALUMINUM
CVC 601 Sputter Tool
(no radiant heating
during pump down)
Pressure = 5mTorr
Power = 2000 Watts
Time = 50 min
Thickness = ~ 1.5um
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
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Rochester Institute of Technology
Microelectronic Engineering
METAL DEPOSITION
Substrate
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 52
Rochester Institute of Technology
Microelectronic Engineering
RECIPES FOR RESIST COAT AND DEVELOP
Level Level
Name
Resist Coat Recipe Develop
Recipe
Resist
Thickness
0 Zero OIR-620 Coat Develop 1.0um
1 Poly 1 OIR-620 Coat Develop 1.0um
2 CC OIR-620 Coat Develop 1.0um
3 Sac Layer S1827 MEMSCOAT1 MEMSDEV1 3.0um
4 Metal 1 S1827 MEMSCOAT2 Hand Develop 4.5um
MEMSCOAT2.rcp no HMDS, 2500rpm, 30sec, Hand Dispense, 110°C, 1min, Exposure for S1827, 525mj/cm2, Focus +2.0, NA=0.48, s=0.45, Hand Develop, no hardbake, no HMDS,
MEMSCOAT1.rcp 4000rpm, 30sec, Hand Dispense, 110°C, 1min Exposure for S1827, 525mj/cm2, Focus +2.0, NA=0.48, s=0.45Then Flood expose wafer edge using black transparency mask thenMEMSDEV.rcp, 200 second develop time, hardbake 140°C
SacrificialLayer
Metal
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 53
Rochester Institute of Technology
Microelectronic Engineering
METAL PHOTO
Substrate
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 54
Rochester Institute of Technology
Microelectronic Engineering
METAL ETCH
Substrate
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 55
Rochester Institute of Technology
Microelectronic Engineering
K&S 780 WAFER SAW
Saw ½ way
through wafer.
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 56
Rochester Institute of Technology
Microelectronic Engineering
WAFER SAW RECIPE
Block 01 - Align on 3nd cut at top of bottom chip, no cuts but shift by -10mm after align
Height 0.80000mm
Cut Depth 0.5000mm (leaving 0.3000 mm of wafer uncut)
Number of cuts = 0000
Block 02 - X cuts (horizontal cuts parallel to wafer flat)
Height 0.80000mm
Cut Depth 0.5000mm (leaving 0.3000 mm of wafer uncut)
Number of cuts = 0027
Block 03 - Align on 3rd at the top of bottom chip, no cuts but shift by -10mm after align
Height 0.80000mm
Cut Depth 0.5000mm (leaving 0.3000 mm of wafer uncut)
Number of cuts = 0000
Block 04 - Y cuts (vertical cuts perpendicular to the wafer flat)
Height 0.80000mm
Cut Depth 0.5000mm (leaving 0.3000 mm of wafer uncut)
Number of cuts = 0027
other parameters on next page….
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 57
Rochester Institute of Technology
Microelectronic Engineering
SAW RECIPE – OTHER PARAMETERS
Blade Exposure 7.4922
Auto Height Rate 499
Spindle speed 20,000
Angle 0.0
Start Cut -33.4
Cut Length 175.00
Index ??
Cut Count ??
X entry speed 2.0
X cutting speed 3.0
Z speed 0.3
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 58
Rochester Institute of Technology
Microelectronic Engineering
AFTER SAWING AND REMOVAL OF GOOD CHIPS
Wafer Sawing Movie
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
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Microelectronic Engineering
WAFER AFTER SAWING READY FOR RELEASE
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 60
Rochester Institute of Technology
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RESIST STRIP AND RELEASE
Substrate
AcetoneIsopropyl AlcoholSlow Pull
or Low power O2 plasma
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 61
Rochester Institute of Technology
Microelectronic Engineering
TEST EQUIPMENT
Manual Prober
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
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Rochester Institute of Technology
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SINGLE RESISTOR SENSOR AMPLIFIER DESIGN
-V
-
+
+V
-V
R1
R4
Vout
-
+
+V
-V
+V
267
0.00004%/°C with gain of 1000 and 100C
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
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Rochester Institute of Technology
Microelectronic Engineering
SINGLE SUPPLY OSCILLATOR (MULTIVIBRATOR)
-
+Vo
C
+V
R2R1
R
VT
+VR3
Vo
t
t1
+V
0
Let R1 = 100K, R2=R3=100K
and +V = 3.3
Then VT = 2.2 when Vo = 3.3
VT = 1.1 when Vo = 0
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 64
Rochester Institute of Technology
Microelectronic Engineering
UNIVERSAL PUMP & FLOW SENSOR ASSEMBLY
1” by 3” PCB 0.0125” thick with 0.005”copper
Pin strip header
Hose nipples
Plastic cover
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 65
Rochester Institute of Technology
Microelectronic Engineering
CROSSECTION
Pin strip header
Hose nipples
ThermosettingGlue on Plastic cover
1” by 3” PCB 0.0125” thick with 0.005”copper
MEMS chip mounted flush with PCB surface, wire bonds from MEMS chip to copper traces
Photoresist (film) channel wallsThickness 50µm to 150µm
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 66
Rochester Institute of Technology
Microelectronic Engineering
AFTER WIRE BONDS, HEADER AND NIPPLES
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 67
Rochester Institute of Technology
Microelectronic Engineering
CLEAR FIELD MASKS
Need dark field masks for Anchor or CC
Otherwise use negative resist
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 68
Rochester Institute of Technology
Microelectronic Engineering
USING NEGATIVE RESIST
1. Coat wafers with n-LOF-2020 Image Reversal Resist, Use COATNLOF recipe on the SSI track
HMDS prime: 140C, Dispense for 30s, Prime for 60sManually dispense photoresistSpin at 2500 RPM, Spin for 60s, Thickness ~2100nm = 2.1umSoft Bake at 110C, Bake for 60s
2. Expose on the ASML Stepper – use same mask as for etch process (clear field)Dose = 66 mJ/cm2 i-line (365nm), Focus = 0, NA = 0.60, Sigma=0.625
3. Develop on SSI Track using recipe DEVNLOFPEB (Image Reversal Bake) at 110C for 60s Spin and dispense developer for 5s, Dispense developer for 5s, Puddle develop for 70s, Spin and rinse for 30s at 1000 RPM. Spin dry for 30s at 3750 RPM, Do not hard bake. It can damage the sidewall profile. Hard Bake time = 0s
4. Etch
5. Remove Photoresist
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 69
Rochester Institute of Technology
Microelectronic Engineering
USING NEGATIVE RESIST
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 70
Rochester Institute of Technology
Microelectronic Engineering
SUMMARY
This project allows students to see the entire process for design, fabrication, packaging and testing of a MEMS based Microsystem.
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 71
Rochester Institute of Technology
Microelectronic Engineering
REFERENCES
1. Dr. Lynn Fuller’s webpage2. more
© November 1, 2017 Dr. Lynn Fuller
Surface MEMS Fabrication Details
Page 72
Rochester Institute of Technology
Microelectronic Engineering
HOMEWORK – FABRICATION DETAILS
1. Draw a series of pictures that show the crossection and layout
for your design project. From starting wafer to test. Not all of
the steps but for most of the steps.
2. Provide a list of all recipes and a short description.
3. What data should be collected ie. at step 7 record oxide
thickness, at step 9 take picture of resolution, at step ? …..
4. Discuss how your device will be packaged.
5. Discuss how the devices you make will be tested. Describe
any electronic circuits