So I know that silicon is the most common semiconductor out there by far. But I also know that there are countless other options; silicon carbide, germanium, SiGe alloy, gallium arsenide, aluminum gallium phosphide, the terrifying-sounding mercury cadmium telluride...
So, what properties would make a device designer choose one over the others? I understand that for LEDs and laser diodes matching the bandgap to give the right photon energy would be one reason, but are there others?
Germanium used to be the semiconductor of choice, but it was booted out by silicon fairly early on, and now it's near impossible to find germanium components. Why is that? Likewise, no one uses selenium rectifiers anymore (though they have more obvious disadvantages, like the ridiculously low reverse breakdown voltage and their physical size).
There's a lot of question marks in this question; I do hope that's not too many. While I am curious about this myself, I'd like to also make it a resource for others to use, so I tried to cover as much ground as possible without straying too far from the topic.