Statement I: At absolute zero the conductivity of semiconductor is zero. \ Statement II: In a semic

Question

Statement I: At absolute zero the conductivity of semiconductor is zero. \ Statement II: In a semiconductor there are no free electrons at any temperature.

Professor PC Thomas Classes · Answer

(b) : In a semiconductor, there are no free electrons at 0 K . So, conductivity is zero. The number of free electrons increases with increase in temperature because with increase in temperature the electron get sufficient energy to cross forbidden band and reach conduction band. But total number of free electrons in a semiconductor is less than that in a conductor.