If we add an impurity that increases the density of

Question

Consider a semiconductor at 295 K with ?ε_gap = 1.1 eV. It is intrinsic, so that excitations involve the valence and conduction bands only.

(a) Roughly what is the density of electrons in the conduction band?

(b) If we add an impurity that increases the density of electrons (the number per cubic meter) in the conduction band tenfold, what will be the density of holes in the valence band?