I feel like I'm still not getting something:
Out of my Atkins textbook:
"Thus, the conventional distinction between an insulator and a semiconductor is related to the band gap and is not an absolute distinction like that between a metal (incomplete bands at T= 0) and a semiconductor (full bands...
Just theory, not a problem.
Is what differentiates a conductor from a semiconductor that the Fermi level has empty orbitals very close in energy to it so that electrons can be mobile in the conduction band?
So what is the largest band gap you can have before you call the material a metal...