Researchers create first functional semiconductor made from graphene
techxplore.com
techxplore.com
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
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.
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.
Beg pardon? The Wright brothers are specifically recognized for the first powered airplane. They started with gliders, but had an engine on one of the later versions.
The Wright Brothers' biggest contribution to flight was in terms of aerodynamics and steering the glider. Adding the engine was arguably the easiest part, but you first had to come up with a glider design giving you enough lift. Even today most people wouldn't be able to do that on their own. Saying the Wright Brothers didn't invent the plane does not take away from those contributions. It simply corrects misinformation and puts them back into a long line of scientists and inventors who all worked on creating what we today know as airplanes.
The comment was strictly about their first plane, their supposed invention. When they flew their first glider, Lilienthal was already dead. His first flights had been 20 years before those of the Wrights! And yes, the Wrights obviously started with the glider just like him (which I was talking about) and only added the motor in later versions. It's known that they studied documents from Lilienthal and others and designed their flying machine based on that. So the idea that they invented it is ridiculous, that's all I was trying to communicate. Adding the engine does not mean they invented the whole thing, but sadly the general public has no idea about this and thinks they were the sole inventors.
They were still extremely skilled engineers, not to take away from that. They were pioneers in their own right. Their glider was superior to Lilienthal's, but that's partly because it was based on the superior biplane design by Chanute and Herring.
Especially when the Wright brothers plane could fly properly and under control, flying 24 miles, including many turns, a year before Dumont could barely manage a few hundred meters in a nearly straight line and ended his flight in an uncontrolled roll.
Dumont made a flight of 50 meters in 1906. Dumont's 1906 plane had no ability to do turns, rolls, or banking, useful maneuvers when you take a flight. It was not something that could be considered a usable airplane.
For decades most orbital rockets took off in an easterly direction, effectively using the earth's rotation as a catapult. Does that disqualify them as successful orbital flights?
Did you take the airplane out, start it up, and take off? Like a modern, independent airplane? Or did you shoot it out of device first, because it wasn't able?
And not even particularly important, by the way. The last time this kind of argument was novel to me was in the mid-nineties at Slashdot.
So yes, it is simple. The Wrights flew without "shooting it out of a device" years before Dumont. The Wright Flyer was also capable of lateral control, like a modern, independent airplane.
https://en.wikipedia.org/wiki/Lawrence_Hargrave
'he should be remembered as an important experimenter and inventor, who "probably did as much to bring about the accomplishment of dynamic flight as any other single individual".'
Lilienthal was certainly important and served as inspiration, but it was the Wright's who really did all the invention and engineering to create what could credibly be called an airplane.
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.
[0]: https://en.m.wikipedia.org/wiki/Radix_economy[1]: https://www.youtube.com/watch?v=rDDaEVcwIJM
Is this a technology that will carry us over a currently uncrossable river?
- better current load capability - better heat dissipation characteristics
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.
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.
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.