Many of these new alternative technologies improve on some parameters (switching speeds or thermal efficiency), but in terms of miniaturization (which also lead

Many of these new alternative technologies improve on some parameters (switching speeds or thermal efficiency), but in terms of miniaturization (which also leads to better switching speeds and thermal efficiency) the established tech (silicon) will rule for quite a while, simply because of the gigantic head start it has. At the end, none of these technologies really provide for a way to have things smaller than an atom, and silicon tech is already approaching the scale of tens of atoms. It would take a while to get other tech to that regime.