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Single Wafer Wet Processing Wafer Thinning Combination Wafer Size Spindle Tooling with PC Program Recipe Only. Chemical wet etching is the final process for thinning of wafers to 70 μ, effecting repair of grinding defects, final thinning, and surface texture control. Standard chemistries are available from chemical companies pre-mixed for established process recipes or chemistries may also be mixed at the point of use. Veeco single wafer technology allows wafer thinning to be performed in a well controlled process, at the lowest cost of ownership. Wafer Thinning Spindle Tooling Veeco wafer thinning tooling is application specific. Gas Seal spindle tooling with no active area contact or combination vacuum hold down with gas seal protection or carrier wafer spindle tooling is readily available for single or multiple size wafers. Veeco tooling approach is field proven to 70 μ thin silicon wafers. Etch Uniformity Control Typical uniformity requirements are < 3%, both within wafer. The key process parameters to achieve this include dispensing, temperature, flow rate, spindle speed, and chamber exhaust. Veeco systems are standard with PC programmable chemical blending with mixing and recirculation tank capability. Uniformity of Silicon Etch (μm) Thickness Change
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Page 1: Single Wafer Wet Processing - Amazon Web Servicesveeco.s3.amazonaws.com/9c89dc2c4afc6fa590b34e75b60f0c0d.pdf · Single Wafer Wet Processing Wafer Thinning Combination Wafer Size Spindle

Single Wafer Wet Processing

Wafer Thinning

Combination Wafer Size Spindle Tooling with PC Program Recipe Only.

Chemical wet etching is the final process for thinning of wafers to 70 μ, effecting repair of grindingdefects, final thinning, and surface texture control. Standard chemistries are available from chemicalcompanies pre-mixed for established process recipes or chemistries may also be mixed at the point ofuse. Veeco single wafer technology allows wafer thinning to be performed in a well controlled process,at the lowest cost of ownership.

Wafer Thinning Spindle ToolingVeeco wafer thinning tooling is application specific. Gas Seal spindle tooling with no active areacontact or combination vacuum hold down with gas seal protection or carrier wafer spindle tooling isreadily available for single or multiple size wafers. Veeco tooling approach is field proven to 70 μ thinsilicon wafers.

Etch Uniformity ControlTypical uniformity requirements are < 3%, both within wafer. The key process parameters to achievethis include dispensing, temperature, flow rate, spindle speed, and chamber exhaust. Veeco systemsare standard with PC programmable chemical blending with mixing and recirculation tank capability.

Uniformity of Silicon Etch(µm)

Thickness Change

Page 2: Single Wafer Wet Processing - Amazon Web Servicesveeco.s3.amazonaws.com/9c89dc2c4afc6fa590b34e75b60f0c0d.pdf · Single Wafer Wet Processing Wafer Thinning Combination Wafer Size Spindle

Surface RoughnessEach application has requirements for surface roughness. In addition to chemistries being optimized for surfacesmoothness or texturing, the single wafer spin processor parameters allow control of desired properties.

Dispensing TechnologyEtch rate and uniformity are optimized by maintaining constant dwelltimes across the wafer surface. This is accomplished by use of nonlinear motion profiles. A hyperbolic profile ensures equal dwell timeacross the wafer, whether dispensing is at the center or edge of a wafer.Speed, acceleration, deceleration, time, and nozzle height are allprogrammed by recipe for highest precision.

Temperature ControlEtch rate and uniformity are optimized in part by etch chemistrytemperature. Veeco systems are engineered with on-the-flytemperature control, which is programmable by process recipe.Chemistry is heated as dispensed, without the use of large batchheaters, which can lead to chemistry degradation over time. Chemistrytemperature control by recipe is enabled by temperature controllerssized according to the required flow rate and temperature rise.

Before Etch After Etch

Page 3: Single Wafer Wet Processing - Amazon Web Servicesveeco.s3.amazonaws.com/9c89dc2c4afc6fa590b34e75b60f0c0d.pdf · Single Wafer Wet Processing Wafer Thinning Combination Wafer Size Spindle

Learn more about Veeco’s single waferprocess capabilities at www.veeco.com/PSP

Veeco Precision Surface Processing185 Gibraltar RoadHorsham, PA 19044 USA+1 215-328-0700

©2017 Veeco Instruments Inc. All rights reserved. Veeco, the Veeco logo, WaferStorm, WaferEtch and WaferChek areeither registered trademarks of Veeco Instruments Inc. in the United States and/or other countries. Patents pending.Veeco reserves the right to change specifications and other product information without notice.

Flow Rate ControlEtch Rate and uniformity are also optimized by stream flow rate control. Veecoprocessors are configured with an on-the-fly flow rate control systems whichenables closed loop chemical flow by each individual processing step. All wettedsurfaces are Teflon and no pumping systems are utilized for clean, reliable, lowmaintenance operation in continuous operations.

Chemical Separation and RecirculationVeeco’s molded chamber contain an internal, programmable, open or closedcollection ring (patent pending) which achieves 99% efficiencies in chemicalcollection with simple gravity drainage. The collection ring enables an in-situ pre-etch clean to remove etch inhibiting contamination or a post etch spray cleanwithout contaminating the re-circulated solution, even with a spray clean!

Chemical Mixture ControlThe etch rate and uniformity are significantly affectedby the etch rate of the chemistry. While there are goodpre-mixed solutions available for both bulk materialremoval and surface texturing, some users prefer to mixtheir own solutions at the point of use and by recipe.Veeco systems may be configured with chemical mixingby recipe from 10,000:1 dilution to ppb levels, withaccuracy greater than that of the concentrate chemical supply.

Customer 1 Customer 2 Customer 3

Etchant HF:HNO3:H

3PO

4:DI KOH Pre-mix Bulk Silicon Etch

Concentration 5:45:30:20 49% Proprietary Mixture

Temperature 20˚C 65˚C 25˚C

Flow Rate 550 ml/minute 550 ml/minute 1,000 ml/minute

Arm Movement Hyperbolic Hyperbolic Hyperbolic

Dispense Type Stream Fan Stream

Single Pass/Re-circulated Re-circulated Re-circulated Re-circulated

Chuck Type Gas Seal Gas Seal Gas Seal

Chuck Speed 300 RPM 500 RPM 750 RPM

Etch Rate 2 µ/minute 0.6 µ/minute 37 µ/minute

Total Thickness Etched 40 µ 5 µ >40 µ

TTV 0% Change 0% Change 0% Change


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