Why does a semicondctor act as an insulator at 0'k and why its conductivity increases with increasing temperature?
Answer Posted / l.anudeep
Basically to flow current we need free electrons.
But all the electrons will be in covalent bonds initially.
If we apply energy the electrons will come out of the covalent bond.There are 3 types of energies 1)thermal 2) electrical 3)optical.Thermal energy is free of cost(room temperature).Thus at 0K the bonds will not break and the electrons will be bounded electrons(they do not conduct current).at room temp(300K) the electrons will break the bonds and come out of it, and now if we apply voltage (+ and -) at 2 ends of SC the current flows.Thus Sc acts as Insulator at 0K and conductor at 300K.
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