Main reason why semiconductor is used and not a "pure" metal for detec Hi, I have question regarding why semiconductor is prefered in the field of radiation detection. I have read that they can be doped and their conductivity can be manipulated, but I cant see why this is not possible with "pure" metals, e.g. copper. Can someone explain this to me? Also, I have read that the energy to create an electron and hole pair is about 3eV for germanium, the band gap is about 0.7eV, so obviously there is other process that require energy to liberate this pair. Which are they? Thank you very much!