High school student building 70's era chip fab in his garage

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kieranhj
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High school student building 70's era chip fab in his garage

Post by kieranhj » Thu Jan 25, 2018 3:57 pm

https://spectrum.ieee.org/semiconductor ... d-circuits

His goal is eventually to clone an Intel 4004 IC. In his garage. I love it! :D
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danielj
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Re: High school student building 70's era chip fab in his garage

Post by danielj » Thu Jan 25, 2018 6:01 pm

That is properly awesome!

d.

crj
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Re: High school student building 70's era chip fab in his garage

Post by crj » Wed Feb 21, 2018 5:55 pm

It is indeed.

For me, though, the really big deal is this part:
To pattern the circuits on his chips, Zeloof uses a trick not available in the 1970s: He’s modified a digital video projector by adding a miniaturizing optical stage. He can then create a mask as a digital image and project it onto a wafer to expose a photoresist. With his current setup Zeloof could create doped features with a resolution of about 1 µm, without the time and expense of creating physical masks (however, without a clean-room setup to prevent contamination, he says 10 µm is the limit for obtaining a reasonable yield of working devices).
The glass plates to make a silicon chip cost tens or hundreds of thousands of pounds. If we've got to the point where that step can be eliminated then small-volume ASIC production has become a possibility. If there was demand for, say, a hundred brand new 8271 FDCs, that demand could be met economically.

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BigEd
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Re: High school student building 70's era chip fab in his garage

Post by BigEd » Wed Feb 21, 2018 6:59 pm

I remember back in the day direct write to wafer using electron beam lithography looked like it might take over the world. (See here, from 1983, and here, from 1980.) But it didn't - that time around. It only really works for low volume, which suits IBM super expensive mainframe chips, and also small re-runs of floppy disk controllers.

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