Sam Zeloof builds integrated circuits in his home garage using DIY lithography and fabrication equipment, and documents the process.
HN commenters call it astounding: he makes working chips with 1970s-level processes from a garage, and they point to it as proof home chip fabrication is possible.
It's totally doable! Although it does take some non-household equipment and chemicals. But much of the equipment you need can be purchased off ebay for relatively cheap.
It's actually a hobby project I'm working on right now, to create some large transistors and simple circuits. My goal is 10um process (aka 1970's technology), but I'd be pretty happy with something a few orders of magnitude higher.
Jeri Ellsworth is the first that I'm aware of having created some large transistors (NMOS process) in her garage and documented the process:
- https://hackaday.com/2010/05/13/transistor-fabrication-so-simple-a-child-can-do-it/
- http://4hv.org/e107_plugins/forum/forum_viewtopic.php?85399.post
And Sam Zeloof very recently did similar:
- https://hackaday.com/2017/02/25/the-fab-lab-next-door-diy-semiconductors/
- Lots of other cool stuff on his blog too, like a SEM he restored in his garage, sputtering experiments, etc: http://sam.zeloof.xyz/
As for me, I'm tackling the maskless lithography step first and repurposing a pico projector with modified optics, laser and translation XY stage. More details being blogged actively here: https://hackaday.io/project/25260-makerfoundry
> Would the physics work at that large scale? It could be a cool way to demonstrate the concepts.
Transistors definitely work at the macro scale (see Jeri and Sam's transistors), but they do have some funky properties. Their switching speed is slow, and due to impurities in the process tend to be…
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/
[2]…
The amount of coorp marketing bullshit was outstanding again:
> The state-of-the-art technology in Bosch's new semiconductor factory in Dresden shows what outstanding results can be achieved when industry and government join forces," said European Commission Vice-President Margrethe Vestager.
who just cites the Bosch press officer, who even dared to mention AI and self-driving cars.
In reality this far away from "state of the art" or "outstanding". The plan is a 65nm fab, now they are still running 130nm for a year already. Their neighbors in Dresden are Infineon with a 90nm fab, and Global Foundries (Ex-AMD) with 22nm. This was once state of the art (some decade ago). Current state of the art is 4-7nm in Taiwan, and Germany/Europe is not even close.
130nm is close the masks which can be produced at home, just not at scale. http://sam.zeloof.xyz/
Some plant parts are state of the art though coming from Dresden. Such as the Ardenne wafer coating machines, which are used in Taiwan also.
http://sam.zeloof.xyz/first-ic/
This is one of the things where the details of the "booting civilization" situation matter a LOT. If you can find a Blu-ray player, it'd be much easier for you to make something like Breaking Taps did- no need for a projector or computer, you could even do this by hand using an optical relay.
However it's VERY hard to make an appropriate UV laser[1], and it's very hard to make a photoresist that works in infrared where a CO2 laser is easy to make. In that case you have to use a projector.
For a while I've wondered how feasible it would be to use an electron microscope to just ablate everything. Shockingly easy to make for such an excellent instrument.
[1]: Ironically the easiest type of laser to make is a UV nitrogen laser, but it's extreme power and short (nanosecond) pulse time mean you can't use it for this: http://www.repairfaq.org/sam/lasercn2.htm#cn2cn20
While possibility of creating ICs in a "homelab" remains years or decades in the future, it is an innovation that is very important to strive for. The world of information has become increasingly dangerous, and trust is in short supply. We need stronger guarantees that our computational hardware is secure and backdoor-free and the best (but not perfect) way of doing it is to manufacture it yourself.
Libre Silicon [1] is one organization that is striving forward and I am hopeful they will make great progress.
Edit: when a high schooler can fabricate ICs in his garage [2], you know with enough effort, a lot of progress can be made on the problem
[1] https://libresilicon.com/
[2] http://sam.zeloof.xyz/first-ic/ https://news.ycombinator.com/item?id=20657398
You got me. That was more of a rhetorical flourish than something I've actually done, or would do. "I haven't done this recently. Or in the past."
Sam Zeloof is doing great things: http://sam.zeloof.xyz/
> Making even the simplest 6502 equivalent by yourself is impossible, forget more complex projects. I feel like this should be urgently addressed, given how important computing is.
I've thought about this, more in the context of post-apocalyptic computing rather than trust, FWIW.
If I were really going to make my own computers from scratch I think clockwork (Clock of the Long Now) or fluidics would probably be the way to go. Maybe electro-mechanical (relays, etc.) or vacuum tubes? We did pretty well with the abacus and the slide rule, eh?