Question

Experiment determine energy band gap semiconductor

Answer 1

In semiconductors the distance b/w the valence and conduction band is less than 3eV.

At room temp. semiconductor devices show very little conductivity as few electrons jump to conduction band.

with increase in temp. the electrons gain enough energy and come out from their lattice site. so there is more free electrons with rise in temp.

the free electrons is equal to the holes. and when electric field is applied the holes moves toward the -ve potential and current due to movement of electron is Ie and current due to movement of hloes is Ih.

So in semiconductor devices the total current is given by..

I = Ie + Ih