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I wish! I've actually looked into it and there's lots of interesting work in academia and garages on small scale, low cost silicon fab [1] as well as the electr
by akiselev 6y ago
I wish! I've actually looked into it and there's lots of interesting work in academia and garages on small scale, low cost silicon fab [1] as well as the electron microscopy necessary to do quality control [2]. Last I checked the state of the art was using regular microscopes with Texas Instruments digital micromirror devices from projectors with basic photoresist and etchant. The DMD reflects light from your light source onto the wafer with the resist and you can control the micromirrors like pixels to only reflect light at the pixels you want to expose the resist. The doping is doable with basic vapor deposition but alignment between steps is brutally hard and the doping requires a lot of tuning and environmental stability to get right so the feature limit is 1 micrometer at best.
I even found a TI 1080p UV DMD and bought a roll of lithographic film to try to get that feature size limit down. My plan was to expose the litho film instead of the wafer directly and build very precise jigs for the film off of a precision machine base I could get for a few grand, with custom built linear motors to move between steps but I got stuck on the physics and math. It looked like I had a solution using neural networks and a DIY laser interferometer as the feedback loop as a shortcut to learning control theory but then got distracted by more urgent matters... c'est la vie
[1] http://sam.zeloof.xyz/category/semiconductor/ http://sam.zeloof.xyz/category/semiconductor/
[2] http://sam.zeloof.xyz/garage-electron-microscopy-first-images/ http://sam.zeloof.xyz/garage-electron-microscopy-first-image...
- CamperBob2 6y agoSome very interesting work there, reminds me of Ben Krasnow's lair. You guys should hang out! I thought the voiceover video for the SEM lithography experiment worked really well ( https://youtu.be/SB94rQtKlKI https://youtu.be/SB94rQtKlKI ). How does the spot size from the SEM compare to the ~1-um resolution you get from the DMD? I assume you're not actually getting 5 nm out of it...?