6 ms·

When we saw a rise in 3d printing, I was very hopeful that a hobbyist movement towards fabricating large-feature ICs would soon arise. Nobody's doing 4nm fabric

When we saw a rise in 3d printing, I was very hopeful that a hobbyist movement towards fabricating large-feature ICs would soon arise. Nobody's doing 4nm fabrication in their garage, I reasoned, but surely we could get to ~10um. As I read more about the dark art of IC fabrication, though, I realized that even this was a faint dream. I had imagined a world of lasers carving troughs, and print heads carefully placing down the lines and doping the silicon, an elegant symphony of modern technology. But the real world is much messier -- every stage involves dangerous and toxic chemicals, processes that are spoiled by a spec of dust in the wrong place, either causing a cascade of reagent failures or a physical impediment to correctness; distressingly analog and oh so messy and built by trial and error and refined by domain experts in ways that are intensely hard to replicate because all the same lessons need to be learned again each time. I'm glad to see the work being done here for hobbyist fabrication, but barring huge leaps and bounds, the gap between the neat lines in Magic and the shiny silicon discs is a vast chasm owned by the material scientists, not the electrical engineers or the software engineers.

foobarian 2y ago
> but surely we could get to ~10um. Well, why not 100um then? It's still way better than discrete components.
- teucris 2y ago
  I’m convinced this is the way to go. Rather than imitating commercial fab techniques, let’s find something that works without the toxic chemistry or vacuum chambers, even if it’s janky at first. 3D printers were janky at first too.
- qwezxcrty 2y ago
  100 um is 4mil, which is the resolution one can get from the cheapest PCB offerings. (e.g. for single digit $ from JLCPCB).
  - ben_w 2y ago
    > 100 um is 4mil Just checking, "4mil"? When I see (or hear) "mil" I assume millimeters, which clearly isn't right here, but I don't know if this is autocorrupt or if this is shorthand for something else I've never seen called this before, say "1e-4 meters"?
    - r2_pilot 2y ago
      A mil in manufacturing is 0.001 inches(in this case 100um =3.937mil).
    - zwog 2y ago
      mil in this context is 1/1000 inch
    - deleted 2y ago
      [deleted]
    - kragen 2y ago
      USAmericans will do anything to avoid using the metric system. To them, "mil" means "milli-inch".
    - qwezxcrty 2y ago
      mil is an unfortunate shorthand for one-thousandth of an inch widely used in the electronics industry.
- Lerc 2y ago
  If you could fit even 9 logic gates into 1 square mm with a construction mechanism that scaled up to 2cm by 2cm you could build a rather capable 8-bit CPU. I do wonder if taking this approach would work better with a novel construction method. Lithography and nasty chemicals are easier for resolution, but nasty chemicals. On the other hand there will always be someone standing by to tell you an FPGA could have done that.
  - fragmede 2y ago
    And someone next to them saying there's a chip that already does that, with someone standing next to them holding a commercial product that does the thing, and someone next to them tell everybody it's all a waste of time. Someone's going to judge what you do regardless. As long as you're not hurting someone else, go build what you want to build, others be damned.
    - Lerc 2y ago
      Totally agree. As creator of a lot of projects where people have asked "Why would you even do that". I wholly encourage build and be damned. I've done Pacman in DCPU-16 asm A HTML/JS desktop environment 8-bit AVR assembler in JavaScript An 8-bit fantasy console with web IDE. and whatever the hell https://c50.fingswotidun.com/ https://c50.fingswotidun.com/ is plus a bunch of other things that really make people wonder if I have any sort of life plan at all.
blackguardx 2y ago
Thin-film transistor circuits can probably approach more of what you are envisioning than silicon integrated circuits. There are even organic semiconductor versions of TFTs that use lower temperatures and liquid chemistry for layer deposition.
atrus 2y ago
It's really expensive or difficult to have a one off object made though, and that's where 3D printing thrived. It fulfills that rapid prototyping itch. People don't even really etch their own pcbs anymore, it's so fast and cheap, let alone spend $10k+ to manufacture a six cent item (maybe!), so there never was enough motivation for a diy movement to make ICs and other nanofabbed stuff
- BizarroLand 2y ago
  Especially when the goal is not the 6 cent item but rather the thing the six cent item makes possible. I would whip out the credit card if I could make 555 timers at home for fun for $1,000. Not sure if I put a second mortgage on my house to have a chance at maybe making one if I didn't screw up too much.
- ysofunny 2y ago
  you're spot on! clearly a big part of why all these tech has been so succesful is also how it's all about investing a lot up front, but eventually being able to mass produce in a ridiculous scale, few industries have such a ratio (possibly pharma?) so it's all about making chips by the hundreds of thousands. it requires a very different approach from any tech intended to make chips by the handful
- marcosdumay 2y ago
  Nobody ever created a reliable self-contained foolproof PCB etching procedure. That's why nobody etches their own PCBs. If there was a box that received supplies and outputted usable PCBs with minimum external mess, a lot of people that currently buy boards would use it instead. (And well, PCB manufacturing is basically the same process as chip fabrication, without the miniaturization. If nobody managed to create a "PCB printer", why do people keep hopping for a "chip printer"?)
  - kragen 2y ago
    Etching your own PCBs has been a common electronics hobbyist activity for 50 years or more. Un-etched one-layer and two-layer PCBs were a standard stock item at every Radio Shack. Local electronics stores stock ferric chloride etchant.
duped 2y ago
University labs (with the right funding) can totally do this, it's just not cheap. My university sold all its fab hardware to another university the year before I was able to take a VLSI class which at the time, had a practical lab. * > As I read more about the dark art of IC fabrication I want to push back on this being a "dark art" - there is no magic in engineering (nb4, any sufficiently advanced technology etc etc). It's a skillset that requires education, experience, and expertise on par with anything we do in other areas of engineering. The stakes are just a little higher than software because you're dealing with the physical world and physical things have tangible costs and/or danger. The thing that may trip people up is that IC fabrication is one of those things that doesn't really have a hobbyist tier. Anything beyond a toy requires multiple people and support staff in addition to gear and raw materials that are hard to get as any old civilian - in addition to the clean room facilities. Like the reason my university closed their lab was partly because the grad/PhD students and professors had moved on, and partly because it was becoming more difficult to source wafers for research institutions that they could actually use (everyone got hired by labs in industry, where they were making their own wafers or buying them wholesale afaict). * iirc only the penultimate project got taped out and fabbed with terrible yields due to time contraints
- jancsika 2y ago
  > I want to push back on this being a "dark art" - there is no magic in engineering (nb4, any sufficiently advanced technology etc etc). It's a skillset that requires education, experience, and expertise on par with anything we do in other areas of engineering. The stakes are just a little higher than software because you're dealing with the physical world and physical things have tangible costs and/or danger. I think "engineering" in software generally means optimizing a path to a targeted set of behaviors so that the piles of garbage underneath don't end up blocking their execution for eternity. Our starting point is therefore different. You ought to somehow be working around all the physical piles of dust and patchwork of fires that must be constantly igniting inside your laser machinery. I picture it something like the mad surgeon in Minority Report, creating a small transient sterile environment to do illegal eye surgery in a room full of filth. In that light your "art" looks "dark."
- ackbar03 2y ago
UnFleshedOne 2y ago
When there is a need (remote space colonies for example), they might need to develop a more robust process that would trade off size and speed of chips for ease of manufacturing.
- ben_w 2y ago
  OTOH, remote space colonies get zero-g manufacturing, along with free vaccum so hard that makes our best artificial vaccum systems seem like a Florida garden during a hurricane in comparison. What they get to do may not help with DIY in a garage on Earth.
  - thesz 2y ago
    Zero-g adds nothing. You cannot even purify silicon in zero-g, you need some-g for impurities to go up and down. The average distance between molecules of the atmosphere is 3.3nm, this is about 10 times of the typical atom diameter. You need 1/1000 of the standard atmosphere pressure to make this distance ten times bigger. Which will pretty much be the hard vacuum at the scale of the atom manipulation.
    - ben_w 2y ago
      > You cannot even purify silicon in zero-g, you need some-g for impurities to go up and down. Only if you're using the purification technique that was developed for use on Earth that takes advantage of Earth's gravity. There's other ways to purify silicon. Off the top of my head and not because it's necessarily a good idea even in zero-g*, there's the Calutron: https://en.wikipedia.org/wiki/Calutron https://en.wikipedia.org/wiki/Calutron > The average distance between molecules of the atmosphere is 3.3nm, this is about 10 times of the typical atom diameter. You need 1/1000 of the standard atmosphere pressure to make this distance ten times bigger. Which will pretty much be the hard vacuum at the scale of the atom manipulation. That's famously how gases differ from liquids and solids, yes. I'm more pointing towards it being easier to control the doping of the semiconductors when you don't need to worry about the presence of oxygen (or water vapour), and that this is a very very clean "clean room" that you get for free without having to filter out the dust** or pollen because there wasn't any in the first place. * it might be cost effective or not, I'm making no claim either way because I don't care enough to try and engineer something like this and then compare it to the alternatives ** depending on where you go in space, of course; I'm just saying you can pick a place without any, you're not obliged to do this e.g. next to an asteroid.
Palomides 2y ago
there's no chance of DIY silicon fabs taking off, but the industry becoming more accessible to hobbyists is way more plausible imho, the deeper problem is that there are just very few situations where you need a custom chip that can't be covered by existing options or FPGAs, and vanishingly few people have the expertise to get anything interesting done even if they had cheap access to fabs (check out tiny tapeout, though!)
- Joel_Mckay 2y ago
  Sure, if one assumes people will focus on traditional CMOS design, and high-volume rapid fab processes. Most people can't even make FPGA that work properly, and YOLO the simulation given metastability is beyond their users understanding. >few people have the expertise to get anything interesting done even if they had cheap access to fabs Chicken or egg problem... a walled garden simply gets fewer visitors, and people with expensive toys tend not to share. =3
didip 2y ago
Engineering problems can be solved with engineering solutions, e.g. better material science that's not toxic (PLA is common now but it was an engineering marvel). As long as there's a problem and there's money to be made, these things you mentioned can be solved.
readyplayernull 2y ago
I would be happy if electronics companies started offering more dense circuits printed on film instead of thick 1mm PCB. There's too much volume wasted on tracks, that could be reduced layering discrete components and there is film that can isolate the heat.
- tdeck 2y ago
  You can get flexible printed circuits (FPC) from vendors like JLCPCB and PCBWay, which are essentially what you describe. https://jlcpcb.com/blog/flex-pcb-available-at-jlcpcb-from-special-offer/ https://jlcpcb.com/blog/flex-pcb-available-at-jlcpcb-from-sp... https://www.pcbway.com/fpc-rigid-flex-pcb/flex-pcb.html https://www.pcbway.com/fpc-rigid-flex-pcb/flex-pcb.html And in case folks reading this don't already know it, multi-layer rigid printed circuit boards are a common technology based on laminating together multiple very thin rigid layers with each layer carrying separate traces.
  - 15155 2y ago
    FPCs have poor electrical characteristics generally.
bob1029 2y ago
> oh so messy and built by trial and error Not only built by trial and error, but also continuously adapted in near real time to deal with new sources of error. The most complicated aspects of semiconductor manufacturing utilize statistical process control to determine the best course of action by relying on large sample sizes. You probably couldn't start up a modern manufacturing line without already having a manufacturing line due to this. Finding viable "hyperparameters" for a photo tool makes training an LLM look like a tutorial. Bootstrapping all of this required direct human involvement with ever-so-careful incremental offloading of these concerns to automation over a period of decades.
- cxr 2y ago
  > Finding viable "hyperparameters" for a photo tool makes training an LLM look like a tutorial. There's generally an unstated (and occasionally explicit, as in this case) reverence from software people for the kind of mythical engineering that goes on in fabs. In reality, if you've had any direct experience with the manufacturing process—and I'm talking about current- or next-gen processes for the most sophisticated mass market devices like those going into flagship smartphones, mining ASICs, GPUs, and critical applications like use in EVs—you know that a bunch of it is in the hands of folks whose most desirable asset in a prospective worker is that they'll accept low pay to eventually get the necessary work done to the prevailing standard best described as "adequate". Valley types especially, but even other software folks would be really surprised by how much of what goes on in fabs is basically the sort of thing that you would expect to see from people plucked from amateur hour. I've posted about this before on HN. Where improvement to existing chipmaker operations is concerned, the fruit hangs so, so low. Elon's biggest, dumbest misstep is not just buying Twitter; it's buying Twitter and not putting an equal or lesser amount of resources instead into gaining control over how his own (and others') chips are made—doing the same thing for the industry that he did with SpaceX for aerospace. Again, because it cannot be emphasized enough: what passes for acceptable in fab operations is bonkers.
  - Teever 2y ago
    This sounds quite interesting. Can you link to some of your previous comments on this subject?
ash-ali 2y ago
If anyone is interested in future small fabs: https://atomicsemi.com/ https://atomicsemi.com/ Looks very promising. Founder is an interesting person.
- LargoLasskhyfv 2y ago
  Can they beat https://www.minimalfab.com/update/news_en/244 https://www.minimalfab.com/update/news_en/244 along with https://www.minimalfab.com/update/news_en/226 https://www.minimalfab.com/update/news_en/226 & https://github.com/mineda-support/ICPS2023_5 https://github.com/mineda-support/ICPS2023_5 -> https://mole99.uber.space/2024/NAND_tutorial/Design%20of%20a%20NAND%20gate%20using%20the%20ICPS%20PDK.html https://mole99.uber.space/2024/NAND_tutorial/Design%20of%20a... -> https://mole99.uber.space/2023/Minimal_Fab/About%20Minimal%20Fab%20and%20the%20ICPS%20PDK.html https://mole99.uber.space/2023/Minimal_Fab/About%20Minimal%2... ?
bozhark 2y ago
metrix had a laser etching rapid pcb prototyping laser in 2013 in seattle. trace routes down to 1mil
- dvdkon 2y ago
  There are multiple approaches to easily making basic single-sided PCBs at home, but the rest is hard: Multi-layer PCBs, vias, through-hole plating, solder mask... Those are all things that even hobbyists need, but generally require annoying chemicals and multiple manual stages. All these things have been done by hobbyists before, but I suppose doing all of this for a single PCB just isn't attractive.
pragma_x 2y ago
FWIW, there _is_ work being done on the hobby front for IC fabrication "at home". We're still far from buying a miniature chip-fab-in-a-box product, but current technology makes yesterday's tech far more affordable. We're on our way. Example: https://www.youtube.com/watch?v=RuVS7MsQk4Y https://www.youtube.com/watch?v=RuVS7MsQk4Y
hammock 2y ago
How big is a spec of dust? What size can you do if you don’t worry about dust? 1000nm? Smaller?
- rnewme 2y ago
  Dust isn't just a single size, it's a giant range[1], and no, even 1 μm process requires a cleanroom, let alone anything smaller. [1] https://www.engineeringtoolbox.com/particle-sizes-d_934.html https://www.engineeringtoolbox.com/particle-sizes-d_934.html
samatman 2y ago
Teaching rocks to think is not for the faint of heart.
tonetegeatinst 2y ago
Another issue is the insane cost for test/fan equipment. Not even for semiconductor stuff but even material testing. Vacuum chambers and vacuum pumps....metrology microscopes.... Cost to grow single crystal boules is insane. Etc....
matheusmoreira 2y ago
We still need this, no matter how hard it is. If we can't make our own computers, we're stuck with the computers made by big companies and those come pwned right off the factory. We'll never be truly free unless we can make our own free computers at home, just like how we can make our own free software at home.
123pie123 2y ago
you could always have a go a programming a FPGA - it's still cool and fairly cheap now eg these guys are putting retro games on to FPGA https://www.analogue.co/developer https://www.analogue.co/developer

foobarian 2y ago

> but surely we could get to ~10um. Well, why not 100um then? It's still way better than discrete components.

teucris 2y ago
I’m convinced this is the way to go. Rather than imitating commercial fab techniques, let’s find something that works without the toxic chemistry or vacuum chambers, even if it’s janky at first. 3D printers were janky at first too.
qwezxcrty 2y ago
100 um is 4mil, which is the resolution one can get from the cheapest PCB offerings. (e.g. for single digit $ from JLCPCB).
- ben_w 2y ago
  > 100 um is 4mil Just checking, "4mil"? When I see (or hear) "mil" I assume millimeters, which clearly isn't right here, but I don't know if this is autocorrupt or if this is shorthand for something else I've never seen called this before, say "1e-4 meters"?
  - r2_pilot 2y ago
    A mil in manufacturing is 0.001 inches(in this case 100um =3.937mil).
  - zwog 2y ago
    mil in this context is 1/1000 inch
  - deleted 2y ago
    [deleted]
  - kragen 2y ago
    USAmericans will do anything to avoid using the metric system. To them, "mil" means "milli-inch".
  - qwezxcrty 2y ago
    mil is an unfortunate shorthand for one-thousandth of an inch widely used in the electronics industry.
Lerc 2y ago
If you could fit even 9 logic gates into 1 square mm with a construction mechanism that scaled up to 2cm by 2cm you could build a rather capable 8-bit CPU. I do wonder if taking this approach would work better with a novel construction method. Lithography and nasty chemicals are easier for resolution, but nasty chemicals. On the other hand there will always be someone standing by to tell you an FPGA could have done that.
- fragmede 2y ago
  And someone next to them saying there's a chip that already does that, with someone standing next to them holding a commercial product that does the thing, and someone next to them tell everybody it's all a waste of time. Someone's going to judge what you do regardless. As long as you're not hurting someone else, go build what you want to build, others be damned.
  - Lerc 2y ago
    Totally agree. As creator of a lot of projects where people have asked "Why would you even do that". I wholly encourage build and be damned. I've done Pacman in DCPU-16 asm A HTML/JS desktop environment 8-bit AVR assembler in JavaScript An 8-bit fantasy console with web IDE. and whatever the hell https://c50.fingswotidun.com/ https://c50.fingswotidun.com/ is plus a bunch of other things that really make people wonder if I have any sort of life plan at all.

blackguardx 2y ago

Thin-film transistor circuits can probably approach more of what you are envisioning than silicon integrated circuits. There are even organic semiconductor versions of TFTs that use lower temperatures and liquid chemistry for layer deposition.

atrus 2y ago

It's really expensive or difficult to have a one off object made though, and that's where 3D printing thrived. It fulfills that rapid prototyping itch. People don't even really etch their own pcbs anymore, it's so fast and cheap, let alone spend $10k+ to manufacture a six cent item (maybe!), so there never was enough motivation for a diy movement to make ICs and other nanofabbed stuff

BizarroLand 2y ago
Especially when the goal is not the 6 cent item but rather the thing the six cent item makes possible. I would whip out the credit card if I could make 555 timers at home for fun for $1,000. Not sure if I put a second mortgage on my house to have a chance at maybe making one if I didn't screw up too much.
ysofunny 2y ago
you're spot on! clearly a big part of why all these tech has been so succesful is also how it's all about investing a lot up front, but eventually being able to mass produce in a ridiculous scale, few industries have such a ratio (possibly pharma?) so it's all about making chips by the hundreds of thousands. it requires a very different approach from any tech intended to make chips by the handful
marcosdumay 2y ago
Nobody ever created a reliable self-contained foolproof PCB etching procedure. That's why nobody etches their own PCBs. If there was a box that received supplies and outputted usable PCBs with minimum external mess, a lot of people that currently buy boards would use it instead. (And well, PCB manufacturing is basically the same process as chip fabrication, without the miniaturization. If nobody managed to create a "PCB printer", why do people keep hopping for a "chip printer"?)
- kragen 2y ago
  Etching your own PCBs has been a common electronics hobbyist activity for 50 years or more. Un-etched one-layer and two-layer PCBs were a standard stock item at every Radio Shack. Local electronics stores stock ferric chloride etchant.

duped 2y ago

University labs (with the right funding) can totally do this, it's just not cheap. My university sold all its fab hardware to another university the year before I was able to take a VLSI class which at the time, had a practical lab. * > As I read more about the dark art of IC fabrication I want to push back on this being a "dark art" - there is no magic in engineering (nb4, any sufficiently advanced technology etc etc). It's a skillset that requires education, experience, and expertise on par with anything we do in other areas of engineering. The stakes are just a little higher than software because you're dealing with the physical world and physical things have tangible costs and/or danger. The thing that may trip people up is that IC fabrication is one of those things that doesn't really have a hobbyist tier. Anything beyond a toy requires multiple people and support staff in addition to gear and raw materials that are hard to get as any old civilian - in addition to the clean room facilities. Like the reason my university closed their lab was partly because the grad/PhD students and professors had moved on, and partly because it was becoming more difficult to source wafers for research institutions that they could actually use (everyone got hired by labs in industry, where they were making their own wafers or buying them wholesale afaict). * iirc only the penultimate project got taped out and fabbed with terrible yields due to time contraints

jancsika 2y ago
> I want to push back on this being a "dark art" - there is no magic in engineering (nb4, any sufficiently advanced technology etc etc). It's a skillset that requires education, experience, and expertise on par with anything we do in other areas of engineering. The stakes are just a little higher than software because you're dealing with the physical world and physical things have tangible costs and/or danger. I think "engineering" in software generally means optimizing a path to a targeted set of behaviors so that the piles of garbage underneath don't end up blocking their execution for eternity. Our starting point is therefore different. You ought to somehow be working around all the physical piles of dust and patchwork of fires that must be constantly igniting inside your laser machinery. I picture it something like the mad surgeon in Minority Report, creating a small transient sterile environment to do illegal eye surgery in a room full of filth. In that light your "art" looks "dark."
ackbar03 2y ago

UnFleshedOne 2y ago

When there is a need (remote space colonies for example), they might need to develop a more robust process that would trade off size and speed of chips for ease of manufacturing.

ben_w 2y ago
OTOH, remote space colonies get zero-g manufacturing, along with free vaccum so hard that makes our best artificial vaccum systems seem like a Florida garden during a hurricane in comparison. What they get to do may not help with DIY in a garage on Earth.
- thesz 2y ago
  Zero-g adds nothing. You cannot even purify silicon in zero-g, you need some-g for impurities to go up and down. The average distance between molecules of the atmosphere is 3.3nm, this is about 10 times of the typical atom diameter. You need 1/1000 of the standard atmosphere pressure to make this distance ten times bigger. Which will pretty much be the hard vacuum at the scale of the atom manipulation.
  - ben_w 2y ago
    > You cannot even purify silicon in zero-g, you need some-g for impurities to go up and down. Only if you're using the purification technique that was developed for use on Earth that takes advantage of Earth's gravity. There's other ways to purify silicon. Off the top of my head and not because it's necessarily a good idea even in zero-g*, there's the Calutron: https://en.wikipedia.org/wiki/Calutron https://en.wikipedia.org/wiki/Calutron > The average distance between molecules of the atmosphere is 3.3nm, this is about 10 times of the typical atom diameter. You need 1/1000 of the standard atmosphere pressure to make this distance ten times bigger. Which will pretty much be the hard vacuum at the scale of the atom manipulation. That's famously how gases differ from liquids and solids, yes. I'm more pointing towards it being easier to control the doping of the semiconductors when you don't need to worry about the presence of oxygen (or water vapour), and that this is a very very clean "clean room" that you get for free without having to filter out the dust** or pollen because there wasn't any in the first place. * it might be cost effective or not, I'm making no claim either way because I don't care enough to try and engineer something like this and then compare it to the alternatives ** depending on where you go in space, of course; I'm just saying you can pick a place without any, you're not obliged to do this e.g. next to an asteroid.

Palomides 2y ago

there's no chance of DIY silicon fabs taking off, but the industry becoming more accessible to hobbyists is way more plausible imho, the deeper problem is that there are just very few situations where you need a custom chip that can't be covered by existing options or FPGAs, and vanishingly few people have the expertise to get anything interesting done even if they had cheap access to fabs (check out tiny tapeout, though!)

Joel_Mckay 2y ago
Sure, if one assumes people will focus on traditional CMOS design, and high-volume rapid fab processes. Most people can't even make FPGA that work properly, and YOLO the simulation given metastability is beyond their users understanding. >few people have the expertise to get anything interesting done even if they had cheap access to fabs Chicken or egg problem... a walled garden simply gets fewer visitors, and people with expensive toys tend not to share. =3

didip 2y ago

Engineering problems can be solved with engineering solutions, e.g. better material science that's not toxic (PLA is common now but it was an engineering marvel). As long as there's a problem and there's money to be made, these things you mentioned can be solved.

readyplayernull 2y ago

I would be happy if electronics companies started offering more dense circuits printed on film instead of thick 1mm PCB. There's too much volume wasted on tracks, that could be reduced layering discrete components and there is film that can isolate the heat.

tdeck 2y ago
You can get flexible printed circuits (FPC) from vendors like JLCPCB and PCBWay, which are essentially what you describe. https://jlcpcb.com/blog/flex-pcb-available-at-jlcpcb-from-special-offer/ https://jlcpcb.com/blog/flex-pcb-available-at-jlcpcb-from-sp... https://www.pcbway.com/fpc-rigid-flex-pcb/flex-pcb.html https://www.pcbway.com/fpc-rigid-flex-pcb/flex-pcb.html And in case folks reading this don't already know it, multi-layer rigid printed circuit boards are a common technology based on laminating together multiple very thin rigid layers with each layer carrying separate traces.
- 15155 2y ago
  FPCs have poor electrical characteristics generally.

bob1029 2y ago

> oh so messy and built by trial and error Not only built by trial and error, but also continuously adapted in near real time to deal with new sources of error. The most complicated aspects of semiconductor manufacturing utilize statistical process control to determine the best course of action by relying on large sample sizes. You probably couldn't start up a modern manufacturing line without already having a manufacturing line due to this. Finding viable "hyperparameters" for a photo tool makes training an LLM look like a tutorial. Bootstrapping all of this required direct human involvement with ever-so-careful incremental offloading of these concerns to automation over a period of decades.

cxr 2y ago
> Finding viable "hyperparameters" for a photo tool makes training an LLM look like a tutorial. There's generally an unstated (and occasionally explicit, as in this case) reverence from software people for the kind of mythical engineering that goes on in fabs. In reality, if you've had any direct experience with the manufacturing process—and I'm talking about current- or next-gen processes for the most sophisticated mass market devices like those going into flagship smartphones, mining ASICs, GPUs, and critical applications like use in EVs—you know that a bunch of it is in the hands of folks whose most desirable asset in a prospective worker is that they'll accept low pay to eventually get the necessary work done to the prevailing standard best described as "adequate". Valley types especially, but even other software folks would be really surprised by how much of what goes on in fabs is basically the sort of thing that you would expect to see from people plucked from amateur hour. I've posted about this before on HN. Where improvement to existing chipmaker operations is concerned, the fruit hangs so, so low. Elon's biggest, dumbest misstep is not just buying Twitter; it's buying Twitter and not putting an equal or lesser amount of resources instead into gaining control over how his own (and others') chips are made—doing the same thing for the industry that he did with SpaceX for aerospace. Again, because it cannot be emphasized enough: what passes for acceptable in fab operations is bonkers.
- Teever 2y ago
  This sounds quite interesting. Can you link to some of your previous comments on this subject?

ash-ali 2y ago

If anyone is interested in future small fabs: https://atomicsemi.com/ https://atomicsemi.com/ Looks very promising. Founder is an interesting person.

LargoLasskhyfv 2y ago
Can they beat https://www.minimalfab.com/update/news_en/244 https://www.minimalfab.com/update/news_en/244 along with https://www.minimalfab.com/update/news_en/226 https://www.minimalfab.com/update/news_en/226 & https://github.com/mineda-support/ICPS2023_5 https://github.com/mineda-support/ICPS2023_5 -> https://mole99.uber.space/2024/NAND_tutorial/Design%20of%20a%20NAND%20gate%20using%20the%20ICPS%20PDK.html https://mole99.uber.space/2024/NAND_tutorial/Design%20of%20a... -> https://mole99.uber.space/2023/Minimal_Fab/About%20Minimal%20Fab%20and%20the%20ICPS%20PDK.html https://mole99.uber.space/2023/Minimal_Fab/About%20Minimal%2... ?

bozhark 2y ago

metrix had a laser etching rapid pcb prototyping laser in 2013 in seattle. trace routes down to 1mil

dvdkon 2y ago
There are multiple approaches to easily making basic single-sided PCBs at home, but the rest is hard: Multi-layer PCBs, vias, through-hole plating, solder mask... Those are all things that even hobbyists need, but generally require annoying chemicals and multiple manual stages. All these things have been done by hobbyists before, but I suppose doing all of this for a single PCB just isn't attractive.

pragma_x 2y ago

FWIW, there _is_ work being done on the hobby front for IC fabrication "at home". We're still far from buying a miniature chip-fab-in-a-box product, but current technology makes yesterday's tech far more affordable. We're on our way. Example: https://www.youtube.com/watch?v=RuVS7MsQk4Y https://www.youtube.com/watch?v=RuVS7MsQk4Y

hammock 2y ago

How big is a spec of dust? What size can you do if you don’t worry about dust? 1000nm? Smaller?

rnewme 2y ago
Dust isn't just a single size, it's a giant range[1], and no, even 1 μm process requires a cleanroom, let alone anything smaller. [1] https://www.engineeringtoolbox.com/particle-sizes-d_934.html https://www.engineeringtoolbox.com/particle-sizes-d_934.html

samatman 2y ago

Teaching rocks to think is not for the faint of heart.

tonetegeatinst 2y ago

Another issue is the insane cost for test/fan equipment. Not even for semiconductor stuff but even material testing. Vacuum chambers and vacuum pumps....metrology microscopes.... Cost to grow single crystal boules is insane. Etc....

matheusmoreira 2y ago

We still need this, no matter how hard it is. If we can't make our own computers, we're stuck with the computers made by big companies and those come pwned right off the factory. We'll never be truly free unless we can make our own free computers at home, just like how we can make our own free software at home.

123pie123 2y ago

you could always have a go a programming a FPGA - it's still cool and fairly cheap now eg these guys are putting retro games on to FPGA https://www.analogue.co/developer https://www.analogue.co/developer