1. NanoFab Trainer Update Nick Reeder, January 18, 2013

2. Update to Wet Etch Code Wet etch rates are now interpolated from look-up tables, with rates increasing as bath temperature increases. – Question: I arbitrarily set each etch rate at 50 C to be double the rate at 20 C. Is that a reasonable first approximation?

3. Update to Dry Etch Code Dry etch rates are now interpolated from look-up tables, with rates dependent on power and pressure. Currently, in the lookup tables: – Rates increase linearly with power. – Rate-versus-pressure curves have profile discussed at our May 17, 2012 meeting:

4. Update to Evaporate Code Deposition rates for evaporation are now interpolated from look-up tables, with rates dependent on voltage and current. Currently, the lookup tables for all evaporable materials hold the same data points, which are correct for Cr: Voltage (kV)Current (mA)Rate (Å/sec) 6.5362 7.5305 7.54010

5. Update to Sputter Code Deposition rates for sputtering are now interpolated from look-up tables, with rates dependent on pressure and power. Currently, the lookup tables for all sputterable materials hold the same data points, which are correct for Al: Pressure (mtorr)Power(W)Rate (Å/sec) 4100.15 4200.09 4500.25 41000.5 41501.6 43002.8 72001.45

6. Menu Updates Added new menu options to let user view (but not edit) spin speed curves, etch-rate lookup tables, and deposition-rate lookup tables. Can extend this code to let the user edit the values too.

7. Other Updates Based on feedback from Summer Institute demo: – Rewrote Define Mask code for smoother operation of sliders. – Added acetone as a wet etchant.

8. To-Do List Implement look-up tables to compute deposition rates for CVD based on user- supplied pressure & temperature. Populate evaporation and sputter look-up tables with values. Fix expose, develop, oxidize, polish code to compute depth from user-supplied values. Continue writing bake code; need realistic values for S 0 and. In expose code, implement diffraction of UV in air and absorption within resist, with dependence on solvent content from bake code. Fix etch code so that (for photoresist) etch rates depend on solvent content from bake code. Fix spin-coat code so that resist does not adhere to underside of horizontal surfaces. Write new code for – Lift-off – Clean – Profilometer Write time-cost-quality code for all operations. Write online help text. Produce videos, photos, text for Tutorial tab.

9. ActivityNot startedPartialComplete Simulation coding CleanX Spin coatX BakeX Mask/Expose/DevelopX EvaporateX Thermal oxidationX CVDX SputterX Wet etchX Dry etchX Lift offX PolishX ImplantX Track time, cost, quality of each processX User -interface coding History with option to revertX Save/open history filesX Edit colorsX User-defined materialsX ProfilometerX Producing embedded media (videos, photos, etc.)X TestingX DocumentationX