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I remember when people were super excited for graphene and nanotubes in semiconductors. What happened to that? Seems like a lot of things stop dead in its track

I remember when people were super excited for graphene and nanotubes in semiconductors. What happened to that? Seems like a lot of things stop dead in its tracks when it comes to mass manufacturing.

deleted 3y ago
[deleted]
WJW 3y ago
Mass manufacturing is really hard, it's not really a surprise that many things that we can do on lab scale can't be made to work (in an economical fashion) at mass production scale.
- adhesive_wombat 3y ago
  We're incredibly lucky that copper and silicon are so (relatively) easy to work with. Imagine if even basic electrical systems needed wires made of rhodium and semiconductors only worked at cryogenic temperatures. We'd never have gotten over the "technological activation energy" in the 1800s.
  - WJW 3y ago
    For sure. When you look at a used car lot or a smartphone for a few hundred dollars, it is easy to forget that they are the product of a system involving (at least!) hundreds of thousands of people working together in a system that has been studied and optimized for decades. Maybe we'll eventually reach consumer grade graphene processors, but if we do it will probably take decades for the technology to advance through the technology readiness levels.
  - amelius 3y ago
    I think about this sometimes. Also, what if Pythagoras' formula didn't exist or was some king of hypothesis or a very long formula: where would technology be?
  - lizknope 3y ago
    Copper was not always easy to work with in semiconductor chips. When I started in the industry in the 1990's all the wiring was aluminum. Articles about copper for wiring were research projects and which company would be the first to get it to mass production. IBM was the first in 1997 and then others followed. https://en.wikipedia.org/wiki/Copper_interconnects https://en.wikipedia.org/wiki/Copper_interconnects That's how technology is. Things start out hard and with a lot of work and time we invent new methods. Aluminum was once worth more than gold. Then we invented new processes of extraction and refinement. https://clintonaluminum.com/aluminum-was-once-worth-more-than-gold-and-silver/ https://clintonaluminum.com/aluminum-was-once-worth-more-tha...
    - magicalhippo 3y ago
      Asianometry recently released a nice video[1] going into the transition to copper interconnects. [1]: https://www.youtube.com/watch?v=XHrQ-Pmvwao https://www.youtube.com/watch?v=XHrQ-Pmvwao
    - gosub100 3y ago
      Can I ask an un-related question? In a CPU with thousands of pins, how come they use N pins for ground, N pins for VCC, when it seems simpler to have continuous bar-shaped contacts? Then pins would only be necessary for signals that actually changed. I see this in computer power supplies as well, they use N separate wires to carry V+ and N more for GND, but if you need more current why not use a thicker wire and only have 2?
      - dmoy 3y ago
        > In a CPU with thousands of pins, how come they use N pins for ground, N pins for VCC, when it seems simpler to have continuous bar-shaped contacts? I can't speak to cpus with thousands of pins, but with significantly smaller chips that often have N>1 vcc or ground, it's typically due to layout convenience. The multiple vcc may be on e.g. opposite sides of the chip, and that makes it easier to route a pure vcc signal to a spot that needs it. It's easier to route outside the chip than inside the chip, because there's more space.
  - m463 3y ago
    I think what happened is we found something rare with interesting properties, then we sort of cost-optimized with other materials until we found something cheaper with similar properties. I think the germanium point contact transistor was sold, but eventually got us via practical methods to the silicon chips we have now. We have had more expensive exotic materials like gallium arsenide. So I think his comment in the article will happen: “Now that we know what structural and electronic properties are needed to achieve the new transport regime discovered in this work, there is good likelihood that we will find earth-abundant alternatives to this rhenium-based material that also show impressive transport properties,” Delor says.
- da_chicken 3y ago
  It's also turned out that carbon nanotubes are toxic in a similar fashion to asbestos. While a completed chip would be sealed, it does raise concerns about the safety of manufacture. Similar concerns have been raised about graphene.
  - runeks 3y ago
    I’m not convinced that’s a problem, since chip fabs require people to wear cleanroom suits anyway.
    - da_chicken 3y ago
      It's possible, but cleanroom suits are primarily designed to protect the product from the employees. They keep foreign contaminants out of the manufacturing environment. They're not necessarily capable of protecting the employees from the hazards of the manufacturing environment itself, nor do they necessarily account for the removal of hazardous material before venting the production area to the atmosphere. It might further add to the costs of the fabrication facility.
      - deleted 3y ago
        [deleted]
      - lazide 3y ago
        Adding hepa filters on exhaust (and issuing respirators) and not just intake would not budge the cost of a chip at all.
  - WJW 3y ago
    Honestly asbestos (and by analogy graphene) would be some of the more benign chemicals involved in semiconductor manufacturing. It regularly uses carcinogens, things that will cause miscarriages in pregnant women and acids strong enough to cause bone damage after being absorbed through the skin. Have a gander at https://en.wikipedia.org/wiki/Health_hazards_in_semiconductor_manufacturing_occupations https://en.wikipedia.org/wiki/Health_hazards_in_semiconducto... for more info.
DeepSeaTortoise 3y ago
I can't help but assume that anything being described as using graphene, carbon nanotubes, crypto, blockchain, bitcoin and - to some degree - AI is a scam. I feel like the only person I've heard talking about graphene and actually demonstrating any practical application is Robert Murray-Smith. This guy is like he fell down the popular science rabbit hole 20 years ago and emerged naked but for a towel screaming "Eureka".
- Teever 3y ago
  That's utterly preposterous. I work with a company that has a couple of patents on a carbon nanotube based sensing system for hydrocarbons. This company is making and selling units every day, like this shit is real man. These units are installed out in the field all around the world and are tied into a dashboard for customers to see if any of their projects are experiencing leaks. I agree that the carbon nano-tech revolution that we were promised by pop-sci writers hasn't materialized but that doesn't mean that it isn't a genuinely useful substance.
formerly_proven 3y ago
Nanotubes perhaps not, but Si nanowires and -sheets are being used for the channel in 3nm-class processes with gate-all-around structure.
ajuc 3y ago
First steam turbines were made in ancient Rome. Took us almost 2000 years to commercialize them :)
- navi0 3y ago
  TIL the Romans invented the first steam engine but didn’t seem to grasp its revolutionary potential and used it mostly as a party trick: https://en.wikipedia.org/wiki/Aeolipile?wprov=sfti1 https://en.wikipedia.org/wiki/Aeolipile?wprov=sfti1
  - phkahler 3y ago
    >> TIL the Romans invented the first steam engine but didn’t seem to grasp its revolutionary potential and used it mostly as a party trick I guess they were civil engineers, not mechanical engineers.
  - lazide 3y ago
    Why automate/industrialize when you have literal slaves?
- scythe 3y ago
  Wikipedia's history of this is very nice: http://en.wikipedia.org/wiki/History_of_the_steam_engine#Precursors http://en.wikipedia.org/wiki/History_of_the_steam_engine#Pre...
Symmetry 3y ago
Normally a manufacturing process is doing well if 90% of the chips on a wafer are usable. Carbon nanotube based circuits manufacture are doing well if 90% of transistors were working. That needs to be solved before they're practical.
hinkley 3y ago
Did we ever categorically prove that nanotubes aren’t the next asbestos? That’s not a small problem.
- I_Am_Nous 3y ago
  Looking into this a bit and I discovered I have carbon nanotubes in my house already [1] and I never would have guessed. Since the nanotubes are pure carbon, I'm not sure it would cause a similar immune response to asbestos, but the "black lung" issue is still likely a risk. Lungs don't like powders in general. 1.https://en.wikipedia.org/wiki/Nano_tape https://en.wikipedia.org/wiki/Nano_tape
- seiferteric 3y ago
  Well it depends, if you plan on grinding your semiconductors into dust and inhaling them, then yes its a problem.
  - hinkley 3y ago
    What I do with my leisure time is none of your business.
- phkahler 3y ago
  >> Did we ever categorically prove that nanotubes aren’t the next asbestos? I'm pretty sure we know they are the next asbestos. So we won't do things with them that tend to produce a bunch of dust for people to inhale.

I remember when people were super excited for graphene and nanotubes in semiconductors. What happened to that? Seems like a lot of things stop dead in its tracks when it comes to mass manufacturing.

deleted 3y ago

[deleted]

WJW 3y ago

Mass manufacturing is really hard, it's not really a surprise that many things that we can do on lab scale can't be made to work (in an economical fashion) at mass production scale.

adhesive_wombat 3y ago
We're incredibly lucky that copper and silicon are so (relatively) easy to work with. Imagine if even basic electrical systems needed wires made of rhodium and semiconductors only worked at cryogenic temperatures. We'd never have gotten over the "technological activation energy" in the 1800s.
- WJW 3y ago
  For sure. When you look at a used car lot or a smartphone for a few hundred dollars, it is easy to forget that they are the product of a system involving (at least!) hundreds of thousands of people working together in a system that has been studied and optimized for decades. Maybe we'll eventually reach consumer grade graphene processors, but if we do it will probably take decades for the technology to advance through the technology readiness levels.
- amelius 3y ago
  I think about this sometimes. Also, what if Pythagoras' formula didn't exist or was some king of hypothesis or a very long formula: where would technology be?
- lizknope 3y ago
  Copper was not always easy to work with in semiconductor chips. When I started in the industry in the 1990's all the wiring was aluminum. Articles about copper for wiring were research projects and which company would be the first to get it to mass production. IBM was the first in 1997 and then others followed. https://en.wikipedia.org/wiki/Copper_interconnects https://en.wikipedia.org/wiki/Copper_interconnects That's how technology is. Things start out hard and with a lot of work and time we invent new methods. Aluminum was once worth more than gold. Then we invented new processes of extraction and refinement. https://clintonaluminum.com/aluminum-was-once-worth-more-than-gold-and-silver/ https://clintonaluminum.com/aluminum-was-once-worth-more-tha...
  - magicalhippo 3y ago
    Asianometry recently released a nice video[1] going into the transition to copper interconnects. [1]: https://www.youtube.com/watch?v=XHrQ-Pmvwao https://www.youtube.com/watch?v=XHrQ-Pmvwao
  - gosub100 3y ago
    Can I ask an un-related question? In a CPU with thousands of pins, how come they use N pins for ground, N pins for VCC, when it seems simpler to have continuous bar-shaped contacts? Then pins would only be necessary for signals that actually changed. I see this in computer power supplies as well, they use N separate wires to carry V+ and N more for GND, but if you need more current why not use a thicker wire and only have 2?
    - dmoy 3y ago
      > In a CPU with thousands of pins, how come they use N pins for ground, N pins for VCC, when it seems simpler to have continuous bar-shaped contacts? I can't speak to cpus with thousands of pins, but with significantly smaller chips that often have N>1 vcc or ground, it's typically due to layout convenience. The multiple vcc may be on e.g. opposite sides of the chip, and that makes it easier to route a pure vcc signal to a spot that needs it. It's easier to route outside the chip than inside the chip, because there's more space.
- m463 3y ago
  I think what happened is we found something rare with interesting properties, then we sort of cost-optimized with other materials until we found something cheaper with similar properties. I think the germanium point contact transistor was sold, but eventually got us via practical methods to the silicon chips we have now. We have had more expensive exotic materials like gallium arsenide. So I think his comment in the article will happen: “Now that we know what structural and electronic properties are needed to achieve the new transport regime discovered in this work, there is good likelihood that we will find earth-abundant alternatives to this rhenium-based material that also show impressive transport properties,” Delor says.
da_chicken 3y ago
It's also turned out that carbon nanotubes are toxic in a similar fashion to asbestos. While a completed chip would be sealed, it does raise concerns about the safety of manufacture. Similar concerns have been raised about graphene.
- runeks 3y ago
  I’m not convinced that’s a problem, since chip fabs require people to wear cleanroom suits anyway.
  - da_chicken 3y ago
    It's possible, but cleanroom suits are primarily designed to protect the product from the employees. They keep foreign contaminants out of the manufacturing environment. They're not necessarily capable of protecting the employees from the hazards of the manufacturing environment itself, nor do they necessarily account for the removal of hazardous material before venting the production area to the atmosphere. It might further add to the costs of the fabrication facility.
    - deleted 3y ago
      [deleted]
    - lazide 3y ago
      Adding hepa filters on exhaust (and issuing respirators) and not just intake would not budge the cost of a chip at all.
- WJW 3y ago
  Honestly asbestos (and by analogy graphene) would be some of the more benign chemicals involved in semiconductor manufacturing. It regularly uses carcinogens, things that will cause miscarriages in pregnant women and acids strong enough to cause bone damage after being absorbed through the skin. Have a gander at https://en.wikipedia.org/wiki/Health_hazards_in_semiconductor_manufacturing_occupations https://en.wikipedia.org/wiki/Health_hazards_in_semiconducto... for more info.

DeepSeaTortoise 3y ago

I can't help but assume that anything being described as using graphene, carbon nanotubes, crypto, blockchain, bitcoin and - to some degree - AI is a scam. I feel like the only person I've heard talking about graphene and actually demonstrating any practical application is Robert Murray-Smith. This guy is like he fell down the popular science rabbit hole 20 years ago and emerged naked but for a towel screaming "Eureka".

Teever 3y ago
That's utterly preposterous. I work with a company that has a couple of patents on a carbon nanotube based sensing system for hydrocarbons. This company is making and selling units every day, like this shit is real man. These units are installed out in the field all around the world and are tied into a dashboard for customers to see if any of their projects are experiencing leaks. I agree that the carbon nano-tech revolution that we were promised by pop-sci writers hasn't materialized but that doesn't mean that it isn't a genuinely useful substance.

formerly_proven 3y ago

Nanotubes perhaps not, but Si nanowires and -sheets are being used for the channel in 3nm-class processes with gate-all-around structure.

ajuc 3y ago

First steam turbines were made in ancient Rome. Took us almost 2000 years to commercialize them :)

navi0 3y ago
TIL the Romans invented the first steam engine but didn’t seem to grasp its revolutionary potential and used it mostly as a party trick: https://en.wikipedia.org/wiki/Aeolipile?wprov=sfti1 https://en.wikipedia.org/wiki/Aeolipile?wprov=sfti1
- phkahler 3y ago
  >> TIL the Romans invented the first steam engine but didn’t seem to grasp its revolutionary potential and used it mostly as a party trick I guess they were civil engineers, not mechanical engineers.
- lazide 3y ago
  Why automate/industrialize when you have literal slaves?
scythe 3y ago
Wikipedia's history of this is very nice: http://en.wikipedia.org/wiki/History_of_the_steam_engine#Precursors http://en.wikipedia.org/wiki/History_of_the_steam_engine#Pre...

Symmetry 3y ago

Normally a manufacturing process is doing well if 90% of the chips on a wafer are usable. Carbon nanotube based circuits manufacture are doing well if 90% of transistors were working. That needs to be solved before they're practical.

hinkley 3y ago

Did we ever categorically prove that nanotubes aren’t the next asbestos? That’s not a small problem.

I_Am_Nous 3y ago
Looking into this a bit and I discovered I have carbon nanotubes in my house already [1] and I never would have guessed. Since the nanotubes are pure carbon, I'm not sure it would cause a similar immune response to asbestos, but the "black lung" issue is still likely a risk. Lungs don't like powders in general. 1.https://en.wikipedia.org/wiki/Nano_tape https://en.wikipedia.org/wiki/Nano_tape
seiferteric 3y ago
Well it depends, if you plan on grinding your semiconductors into dust and inhaling them, then yes its a problem.
- hinkley 3y ago
  What I do with my leisure time is none of your business.
phkahler 3y ago
>> Did we ever categorically prove that nanotubes aren’t the next asbestos? I'm pretty sure we know they are the next asbestos. So we won't do things with them that tend to produce a bunch of dust for people to inhale.