Submitted via IRC for Bytram
The vast majority of computing devices today are made from silicon, the second most abundant element on Earth, after oxygen. Silicon can be found in various forms in rocks, clay, sand, and soil. And while it is not the best semiconducting material that exists on the planet, it is by far the most readily available. As such, silicon is the dominant material used in most electronic devices, including sensors, solar cells, and the integrated circuits within our computers and smartphones.
Now MIT engineers have developed a technique to fabricate ultrathin semiconducting films made from a host of exotic materials other than silicon. To demonstrate their technique, the researchers fabricated flexible films made from gallium arsenide, gallium nitride, and lithium fluoride—materials that exhibit better performance than silicon but until now have been prohibitively expensive to produce in functional devices.
The new technique, researchers say, provides a cost-effective method to fabricate flexible electronics made from any combination of semiconducting elements, that could perform better than current silicon-based devices.
"We've opened up a way to make flexible electronics with so many different material systems, other than silicon," says Jeehwan Kim, the Class of 1947 Career Development Associate Professor in the departments of Mechanical Engineering and Materials Science and Engineering. Kim envisions the technique can be used to manufacture low-cost, high-performance devices such as flexible solar cells, and wearable computers and sensors.
and see https://phys.org/news/2018-10-cost-effective-method-semiconducting-materials-outperform.html#nRlv for a more readable summary
Source: http://dx.doi.org/10.1038/s41563-018-0176-4
(Score: 2) by VLM on Tuesday October 16 2018, @12:04PM
There are other inherent problems. Off the top of my head for GaAs... Can't do CMOS designs because they can't make P-type transistors or maybe it was N-type something to do with ridiculous ratio of electron/hole mobility. Can't make an oxide layer (for MOS transistors) by spraying oxygen and letting natural oxide layer form (gotta CVD something else).
GaAs makes really cool ultra high speed bipolar transistors but you can't just copy the masks from a current CPU to a GaAs process and expect them to work; they won't. Back to bipolar ECL or TTL complete redesign maybe. Of course a ECL design modern CPU would take something like a nuclear reactor to power it (and cool it)
Gallium is rarer but cheaper than gold, so there's that issue. That "cheaper than gold" thing will turn around if you make solar cells out of it.
GaAs makes nice microwave ICs; but there are non-economic reasons we won't see CPUs soon.