> What's All This About Gallium Arsenide?

I was going to say, gallium arsenide was the future of computing in the mid-80s.

It's still used in certain analog electronics, mostly microwave.  GaN and SiGe is also used.

wrote:

Yeah. I had the impression that the semiconductor industry was still forcing silicon to be its bitch.

Silicon is still easier to fabricate than anything else and since the dimensions have gotten so small, speed has been enhanced far beyond where it was previously.  The reason Cray wanted to use GaAs was that the transistors could operate at over 100Ghz, but now that is exactly where silicon is, so there is no good reason to use it for digital electronics.  (note that large circuits such as CPUs and GPUs made of many transistors can't actually run this fast because of propagation delay and the lengths of critical paths).