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Can New Metal-Air Transistors Replace Semiconductors and Continue Moore's Law? (ieee.org)
Will Moore's law really come to an end by 2025? Maybe not...
An anonymous reader quotes IEEE Spectrum: [R]esearchers at RMIT University in Melbourne, Australia, believe a metal-based field emission air channel transistor (ACT) they have developed could maintain transistor doubling for another two decades. The ACT device eliminates the need for semiconductors. Instead, it uses two in-plane symmetric metal electrodes (source and drain) separated by an air gap of less than 35 nanometers, and a bottom metal gate to tune the field emission. The nanoscale air gap is less than the mean-free path of electrons in air, hence electrons can travel through air under room temperature without scattering...
Using metal and air in place of semiconductors for the main components of the transistor has a number of other advantages, says Shruti Nirantar, a Ph.D. candidate in RMIT's Functional Materials and Microsystems Research Group. Fabrication becomes essentially a single-step process of laying down the emitter and collector and defining the air gap. And though standard silicon fabrication processes are employed in producing ACTs, the number of processing steps are far fewer, given that doping, thermal processing, oxidation, and silicide formation are unnecessary. Consequently, production costs should be cut significantly. In addition, replacing silicon with metal means these ACT devices can be fabricated on any dielectric surface, provided the underlying substrate allows effective modulation of emission current from source to drain with a bottom-gate field. "Devices can be built on ultrathin glass, plastics, and elastomers," says Nirantar. "So they could be used in flexible and wearable technologies."
The article also suggests ACT devices could become important in space exploration, since electrons would be unaffected by extraterrestrial vacuums and radiation.
Nirantar was lead author on a new paper published in Nano Letters, and believes that their new approach "means we can stop pursuing miniaturization, and instead focus on compact 3D architecture, allowing more transistors per unit volume."
An anonymous reader quotes IEEE Spectrum: [R]esearchers at RMIT University in Melbourne, Australia, believe a metal-based field emission air channel transistor (ACT) they have developed could maintain transistor doubling for another two decades. The ACT device eliminates the need for semiconductors. Instead, it uses two in-plane symmetric metal electrodes (source and drain) separated by an air gap of less than 35 nanometers, and a bottom metal gate to tune the field emission. The nanoscale air gap is less than the mean-free path of electrons in air, hence electrons can travel through air under room temperature without scattering...
Using metal and air in place of semiconductors for the main components of the transistor has a number of other advantages, says Shruti Nirantar, a Ph.D. candidate in RMIT's Functional Materials and Microsystems Research Group. Fabrication becomes essentially a single-step process of laying down the emitter and collector and defining the air gap. And though standard silicon fabrication processes are employed in producing ACTs, the number of processing steps are far fewer, given that doping, thermal processing, oxidation, and silicide formation are unnecessary. Consequently, production costs should be cut significantly. In addition, replacing silicon with metal means these ACT devices can be fabricated on any dielectric surface, provided the underlying substrate allows effective modulation of emission current from source to drain with a bottom-gate field. "Devices can be built on ultrathin glass, plastics, and elastomers," says Nirantar. "So they could be used in flexible and wearable technologies."
The article also suggests ACT devices could become important in space exploration, since electrons would be unaffected by extraterrestrial vacuums and radiation.
Nirantar was lead author on a new paper published in Nano Letters, and believes that their new approach "means we can stop pursuing miniaturization, and instead focus on compact 3D architecture, allowing more transistors per unit volume."
Besides home and professional appliances are fast and small enough today, even scientific appliances are "good enough" today...
This reminds me of what happened with NAND (i.e. flash memory) a few years ago. Ever-smaller transistors hit a wall due to endurance problems (each one could only be reprogrammed a few hundred/thousand times), so they went back to larger transistors but started stacking them into layers. Now we're at ~96 layers, and it's expected that a few thousand layers is feasible.
The problem with layering in CPUs is how hot each layer gets, and adding new layers is unlikely to help single-core performance beyond what cache can do. So, we're going to end up with low-clockspeed (to minimize heat) thousand-core CPUs... which will actually be perfect for GPUs, not so much for that single-threaded productivity task. I could also see this being used for HBM, which is already stacked.
Corruption is convincing someone that the selfless ideal is the same as their selfish ideal.
>"The nanoscale air gap is less than the mean-free path of electrons in air, hence electrons can travel through air under room temperature without scattering... "
And what about when not at room temperature? Seems like that little disclaimer could be what makes the whole thing impractical. A chip/board isn't going to be made up of ONLY these "metal-air" transistors, so it is going to generate a significant amount of heat or be near something that does. Plus, there is the overall environment in which the device will be used that needs to be considered. The article doesn't elaborate on this at all.
Why do Slashdot editors insist on making headlines into questions that aren't answered in the article?
Perhaps they were hoping to stimulate a discussion between knowledgeable posters, one which weighed the pros and cons of this new (take on) tech, and perhaps arrived at an answer to that question. They might also touch on other, unasked, questions such as whether such tech is desirable, and what we might use it for - something a couple of people have attempted.
The story is, "Researchers believe new metal-air transistors could continue Moore's Law". It isn't a debate on this belief of those researchers.
"It", whatever "it" might be, may not be a debate about the belief of the researchers but if not it's almost certainly a debate about the reasons for their belief. I'd suspect most people who browse here would instinctively fill in the blanks: most, not all - there's always a few who come here to find something to be outraged about, and they can usually find something, then rage about it, while contributing absolutely zero to the discussion.
Oh, wait - this is a click bait tactic used to make something seem more interesting than it really is...
I'm sorry you find this story about new technology uninteresting. Leaving aside the possible reasons for that, one still has to wonder at your expectations when you label the summary as 'click bait'. What do you think people come here for, other than the comments, if not to click on the links to the stories behind the headlines? Click bait kind of implies the article is about nothing and that's certainly not the case here ... well, in my opinion anyway.
I'll will add, my main skepticism about the article was regarding the following: "Devices can be built on ultrathin glass, plastics, and elastomers... So they could be used in flexible and wearable technologies." Hmm, 35nm airgaps in bendable materials - that sounds like a recipe for errors to me, and that's assuming they can solve the electrode tip melting problem. However, the timeline given in the article is, if not 'realistic', long enough that one cannot discount their ideas and short enough that it gives us something to look forward to. I for one will be interested to see how they progress!
Moore's Law potentially has a long way to run - because semiconductors are still only a few layers thick in the Z axis and there are a lot more doublings left before we're dealing with "chips" that are solid circuitry feet on a side. Non vacuum "vacuum tubes" are far less sensitive to high temperatures than semiconductors, so building 3-D structures of them won't have as much of a cooling problem. (You still need to dissipate all the heat, but you can let the structure get 'way hotter to encourage it to migrate out.)
Single Threading speed may be falling off its free ride on Moore's Law-like exponential scaling, as speed-of-light and electron-size leakage limits raise a wall. (Going 3-D will help some, by shortening paths, but not by a lot.) But lots of really useful computations are massively parallelizable. The should drive continued manufacture and deployment of higher-switch-count devices as the technology is developed and yields are brought up.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way