5 ms·

Researchers create first functional semiconductor made from graphene

146 points by wglb 3y ago

mdaniel 3y ago
original source discussion: https://news.ycombinator.com/item?id=38878780 https://news.ycombinator.com/item?id=38878780
ptek 3y ago
With 5nm silicon process, I wonder where this is going to start with retooling and building new machines? I'm guessing they will start with 8bit RISC cpus with maybe the first 128 bytes as a data cache which could also be used as extra registers? It will be great having a lot of expired patents and 50+ years of silicon work to build on, Machine Learning tools and free operating systems (NetBSD, Linux) I hope they do it all again, I want to relive the C64, Amiga and 680x0 era again.
- thijson 3y ago
  This will start with small devices used in power electronics likely. There are faster materials than silicon, but they still aren't used for highly integrated digital logic due to cost.
- logicchains 3y ago
  If starting from scratch with new tooling, I wonder if they'll consider ternary, which is theoretically more efficient than binary (as it's closer to the optimal encoding: e-ary).
  - BoiledCabbage 3y ago
    I believe it, but do you have any links to somewhere discussing why e-ary is the optimal encoding?
    - f_devd 3y ago
      It's likely a reference to the radix economy [0], however it's actually very minor for the cases where it works. And in "the best way to count"[1] there compelling arguments as to why the formulation used on Wikipedia is not necessarily correct for arbitrary precision numbers as well as being bad for human notation compared to binary. [0]: https://en.m.wikipedia.org/wiki/Radix_economy[1] https://en.m.wikipedia.org/wiki/Radix_economy[1]: https://www.youtube.com/watch?v=rDDaEVcwIJM https://www.youtube.com/watch?v=rDDaEVcwIJM
      - akoboldfrying 3y ago
        That was an interesting read, thanks. I'm not convinced that the "cost" of a b-ary digit is appropriately modelled as exactly b in all circumstances, though it is in the example of minimising the average length of time a caller must wait when using a phone menu system.
  - ahf8Aithaex7Nai 3y ago
    It's even closer to pi-ary
  - NegativeK 3y ago
    I can't believe that they'd do that, since it'd mean rewriting huge swaths of existing software.
  - deleted 3y ago
    [deleted]
bilsbie 3y ago
How this made? Still with lithography?
crakenzak 3y ago
Someone please make me excited about this, what can we potentially see from this? How soon until potential commercialization? Is this a technology that will carry us over a currently uncrossable river?
- aabhay 3y ago
  Graphene has been a long standing aspiration in semiconductor materials science: - better current load capability - better heat dissipation characteristics
  - sim7c00 3y ago
    sorry for my being 8 year old, but, does this better current capacity mean it can go faster? and the less heat problems mean it can do so without being cooled riduculously? (i.e. faster consumer products??)
    - droopyEyelids 3y ago
      Computing with graphene is still sci-fi territory, making a semiconductor only allows you to make transistors, not to necessarily make billions of transistors at nano-scales. On the larger physical scale, transistors are used for stuff like mosfets and switching power supplies. You might have noticed the new generation of Gallium Nitride (another semiconductor) USB chargers. They improve over silicon in every important dimension, I think, with a higher breakdown voltage, lower on resistance, higher electron mobility (which is what limits the speed it can cycle). The gallium nitride chargers (when well engineered) waste less power, meaning they don't get as hot, and can be built much smaller for a given output. I am not an engineer or a materials scientist, but I think graphene is better in thermal conductivity and electron mobility than GaN, but a semiconductor would probably have a smaller bandgap, because graphene naturally doesn't have much of one at all, meaning it'd have a smaller operating range in temperature and voltage.
    - magicalhippo 3y ago
      A major problem with current ICs, which gets much worse in 3D (stacked etc) designs, is keeping the transistors cool. The transistor has a maximum operating junction temperature[1] which is limited by material and process. Higher density chips make it difficult to extract the generated heat, in order to keep those junctions cool. The heat is generated when the transistors switch from either on to off or vice versa, due to all normal conductors having some resistance, and switching a transistor involves sending or draining a small amount of current to its control element called the gate. Thus switching faster means more heat. More transistors in the same area all switching means more heat. So either by making it easier to wick away the heat, or by tolerating higher junction temperatures, a different material to silicon might allow for higher density or faster switching before heat becomes an issue. Of course there are other obstacles to increasing density and frequency, so just because a material has better thermal properties doesn't imply it'll allow for higher density or frequency. [1]: https://en.wikipedia.org/wiki/Junction_temperature https://en.wikipedia.org/wiki/Junction_temperature
deleted 3y ago
[deleted]
rustcleaner 3y ago
Incept running GrapheneOS on graphene dies.
vanderZwan 3y ago
> "To me, this is like a Wright brothers moment," de Heer said. "They built a plane that could fly 300 feet through the air. But the skeptics asked why the world would need flight when it already had fast trains and boats. But they persisted, and it was the beginning of a technology that can take people across oceans." Tangent: I always find comparisons to the Wright brothers kind of awkward, because everyone seems to overlook their subsequent patent war and how much damage that did to the aviation industry in general (tangent: similarly Edison really really stifled early innovation in lightbulb technology with patent trolling. Philips became as big as it is because there was a decade in the 19th century where the Netherlands didn't recognize patent laws, so was free to steal and combine every innovation out there. They also employed highly motivated former rivals of Edison whom the latter had put out of business) Anyway, with that side-track out of the way: I don't want to sound to negative, I do hope this is the breakthrough it's hyped up to be! [0] https://en.wikipedia.org/wiki/Wright_brothers_patent_war https://en.wikipedia.org/wiki/Wright_brothers_patent_war
- w-m 3y ago
  Tangent on your tangent: I always find it awkward that people name the Wright brothers as the inventors of the airplane, and keep forgetting Otto Lilienthal. The Wright brothers engineered a control system, that’s nice and all, but pretty boring, iterative work. Lilienthal studied birds, wrote the book on how wings work, produced the first airplanes and was the first person to make well-documented, repeated, successful flights with gliders. In my view these were much more difficult steps and much more important work. Lilienthals life is super interesting, but even his namesake museum in his hometown of Anklam is rather pitiful.
  - trompetenaccoun 3y ago
    Same with Edison and "his" lightbulb, he wasn't actually the first to invent it. He wasn't even the first in his company, that would have been Joseph Swan - as determined by the courts at the time. Swan held the patent and Edison lost the case. Afterwards the two merged their businesses into the 'Edison & Swan United Electric Light Company'. With most great inventions, there usually isn't a single person who came up with them. It's a long process from the first idea to building a working prototype. Lilienthal was definitely one of those great pioneers and it's sad his name isn't as well remembered as that of the Wrights. He was the first in history that we have evidence for to ever fly a glider. The Wright "plane" wasn't anything other than a glider, although they arguably did improve on the concept. Still, it's sad how in the memory of the general public, most of the time there's only a single name for big inventions and it's even the wrong one most of the time.
Xeamek 3y ago
For a second I thought that this conductor somehow supports functional programming instead
__lbracket__ 3y ago
Graphene will firmly remain in the land of "..it promises to transform the semiconductor industry " than actually causing the said transformation !
- jachee 3y ago
  I’m still holding out for the Diamond Age.
  - the__alchemist 3y ago
    The lilies sprouted from a stadium-sized cut-crystal vase, the Diamond Palace, which was open to the public. Tourists, aerobicizing pensioners, and ranks of uniformed schoolchildren marched through it year in and year out, peering through walls of glass (actually solid diamond, which was cheaper) at various phases of the molecular disassembly line that was Source Victoria.
- adrian_b 3y ago
  After this advancement, it is very likely that this claim has become false. I used to think like this, because the previous methods of producing graphene were completely impractical for making integrated circuits. This new method developed by a team at Georgia Tech together with a Chinese team, works in a completely different way. Starting from a silicon carbide wafer suitable for integrated circuits, a superficial layer of carbon is made by evaporating the silicon atoms that are close to the surface. Then the carbon layer is crystallized into graphene. This process makes high-quality semiconducting monocrystalline graphene suitable for making semiconductor devices. The main challenge that remains is to find a way to make high-quality metallic ohmic contacts to the graphene, because the metallic contacts with chromium that have been used now have a high Shottky barrier voltage, and also to make high-quality lightly doped regions of both p and n polarities, because only one high-quality polarity has been demonstrated yet. There is a high probability that these problems can be solved now, when a good substrate has become available, which was the hardest problem that prevented the use of graphene.

146 points by wglb 3y ago

original source discussion: https://news.ycombinator.com/item?id=38878780 https://news.ycombinator.com/item?id=38878780

ptek 3y ago

With 5nm silicon process, I wonder where this is going to start with retooling and building new machines? I'm guessing they will start with 8bit RISC cpus with maybe the first 128 bytes as a data cache which could also be used as extra registers? It will be great having a lot of expired patents and 50+ years of silicon work to build on, Machine Learning tools and free operating systems (NetBSD, Linux) I hope they do it all again, I want to relive the C64, Amiga and 680x0 era again.

thijson 3y ago
This will start with small devices used in power electronics likely. There are faster materials than silicon, but they still aren't used for highly integrated digital logic due to cost.
logicchains 3y ago
If starting from scratch with new tooling, I wonder if they'll consider ternary, which is theoretically more efficient than binary (as it's closer to the optimal encoding: e-ary).
- BoiledCabbage 3y ago
  I believe it, but do you have any links to somewhere discussing why e-ary is the optimal encoding?
  - f_devd 3y ago
    It's likely a reference to the radix economy [0], however it's actually very minor for the cases where it works. And in "the best way to count"[1] there compelling arguments as to why the formulation used on Wikipedia is not necessarily correct for arbitrary precision numbers as well as being bad for human notation compared to binary. [0]: https://en.m.wikipedia.org/wiki/Radix_economy[1] https://en.m.wikipedia.org/wiki/Radix_economy[1]: https://www.youtube.com/watch?v=rDDaEVcwIJM https://www.youtube.com/watch?v=rDDaEVcwIJM
    - akoboldfrying 3y ago
      That was an interesting read, thanks. I'm not convinced that the "cost" of a b-ary digit is appropriately modelled as exactly b in all circumstances, though it is in the example of minimising the average length of time a caller must wait when using a phone menu system.
- ahf8Aithaex7Nai 3y ago
  It's even closer to pi-ary
- NegativeK 3y ago
  I can't believe that they'd do that, since it'd mean rewriting huge swaths of existing software.
- deleted 3y ago
  [deleted]

bilsbie 3y ago

How this made? Still with lithography?

crakenzak 3y ago

Someone please make me excited about this, what can we potentially see from this? How soon until potential commercialization? Is this a technology that will carry us over a currently uncrossable river?

aabhay 3y ago
Graphene has been a long standing aspiration in semiconductor materials science: - better current load capability - better heat dissipation characteristics
- sim7c00 3y ago
  sorry for my being 8 year old, but, does this better current capacity mean it can go faster? and the less heat problems mean it can do so without being cooled riduculously? (i.e. faster consumer products??)
  - droopyEyelids 3y ago
    Computing with graphene is still sci-fi territory, making a semiconductor only allows you to make transistors, not to necessarily make billions of transistors at nano-scales. On the larger physical scale, transistors are used for stuff like mosfets and switching power supplies. You might have noticed the new generation of Gallium Nitride (another semiconductor) USB chargers. They improve over silicon in every important dimension, I think, with a higher breakdown voltage, lower on resistance, higher electron mobility (which is what limits the speed it can cycle). The gallium nitride chargers (when well engineered) waste less power, meaning they don't get as hot, and can be built much smaller for a given output. I am not an engineer or a materials scientist, but I think graphene is better in thermal conductivity and electron mobility than GaN, but a semiconductor would probably have a smaller bandgap, because graphene naturally doesn't have much of one at all, meaning it'd have a smaller operating range in temperature and voltage.
  - magicalhippo 3y ago
    A major problem with current ICs, which gets much worse in 3D (stacked etc) designs, is keeping the transistors cool. The transistor has a maximum operating junction temperature[1] which is limited by material and process. Higher density chips make it difficult to extract the generated heat, in order to keep those junctions cool. The heat is generated when the transistors switch from either on to off or vice versa, due to all normal conductors having some resistance, and switching a transistor involves sending or draining a small amount of current to its control element called the gate. Thus switching faster means more heat. More transistors in the same area all switching means more heat. So either by making it easier to wick away the heat, or by tolerating higher junction temperatures, a different material to silicon might allow for higher density or faster switching before heat becomes an issue. Of course there are other obstacles to increasing density and frequency, so just because a material has better thermal properties doesn't imply it'll allow for higher density or frequency. [1]: https://en.wikipedia.org/wiki/Junction_temperature https://en.wikipedia.org/wiki/Junction_temperature

deleted 3y ago

[deleted]

rustcleaner 3y ago

Incept running GrapheneOS on graphene dies.

vanderZwan 3y ago

> "To me, this is like a Wright brothers moment," de Heer said. "They built a plane that could fly 300 feet through the air. But the skeptics asked why the world would need flight when it already had fast trains and boats. But they persisted, and it was the beginning of a technology that can take people across oceans." Tangent: I always find comparisons to the Wright brothers kind of awkward, because everyone seems to overlook their subsequent patent war and how much damage that did to the aviation industry in general (tangent: similarly Edison really really stifled early innovation in lightbulb technology with patent trolling. Philips became as big as it is because there was a decade in the 19th century where the Netherlands didn't recognize patent laws, so was free to steal and combine every innovation out there. They also employed highly motivated former rivals of Edison whom the latter had put out of business) Anyway, with that side-track out of the way: I don't want to sound to negative, I do hope this is the breakthrough it's hyped up to be! [0] https://en.wikipedia.org/wiki/Wright_brothers_patent_war https://en.wikipedia.org/wiki/Wright_brothers_patent_war

w-m 3y ago
Tangent on your tangent: I always find it awkward that people name the Wright brothers as the inventors of the airplane, and keep forgetting Otto Lilienthal. The Wright brothers engineered a control system, that’s nice and all, but pretty boring, iterative work. Lilienthal studied birds, wrote the book on how wings work, produced the first airplanes and was the first person to make well-documented, repeated, successful flights with gliders. In my view these were much more difficult steps and much more important work. Lilienthals life is super interesting, but even his namesake museum in his hometown of Anklam is rather pitiful.
- trompetenaccoun 3y ago
  Same with Edison and "his" lightbulb, he wasn't actually the first to invent it. He wasn't even the first in his company, that would have been Joseph Swan - as determined by the courts at the time. Swan held the patent and Edison lost the case. Afterwards the two merged their businesses into the 'Edison & Swan United Electric Light Company'. With most great inventions, there usually isn't a single person who came up with them. It's a long process from the first idea to building a working prototype. Lilienthal was definitely one of those great pioneers and it's sad his name isn't as well remembered as that of the Wrights. He was the first in history that we have evidence for to ever fly a glider. The Wright "plane" wasn't anything other than a glider, although they arguably did improve on the concept. Still, it's sad how in the memory of the general public, most of the time there's only a single name for big inventions and it's even the wrong one most of the time.

Xeamek 3y ago

For a second I thought that this conductor somehow supports functional programming instead

__lbracket__ 3y ago

Graphene will firmly remain in the land of "..it promises to transform the semiconductor industry " than actually causing the said transformation !

jachee 3y ago
I’m still holding out for the Diamond Age.
- the__alchemist 3y ago
  The lilies sprouted from a stadium-sized cut-crystal vase, the Diamond Palace, which was open to the public. Tourists, aerobicizing pensioners, and ranks of uniformed schoolchildren marched through it year in and year out, peering through walls of glass (actually solid diamond, which was cheaper) at various phases of the molecular disassembly line that was Source Victoria.
adrian_b 3y ago
After this advancement, it is very likely that this claim has become false. I used to think like this, because the previous methods of producing graphene were completely impractical for making integrated circuits. This new method developed by a team at Georgia Tech together with a Chinese team, works in a completely different way. Starting from a silicon carbide wafer suitable for integrated circuits, a superficial layer of carbon is made by evaporating the silicon atoms that are close to the surface. Then the carbon layer is crystallized into graphene. This process makes high-quality semiconducting monocrystalline graphene suitable for making semiconductor devices. The main challenge that remains is to find a way to make high-quality metallic ohmic contacts to the graphene, because the metallic contacts with chromium that have been used now have a high Shottky barrier voltage, and also to make high-quality lightly doped regions of both p and n polarities, because only one high-quality polarity has been demonstrated yet. There is a high probability that these problems can be solved now, when a good substrate has become available, which was the hardest problem that prevented the use of graphene.