Question

n n-type semiconductor the impurity provides
(a) an excess of holes
(b) an excess of electrons
(c) sufficient number of electrons (d) less number of electrons​

Answer 1

Answer :

In n-type semiconductors the impurity provides an excess of holes.

Learn More :

★ In semiconductors, the gap between the valence band and conduction band is small, some electrons may jump to conduction band show some conductivity.

★ Doping : It is a process of adding an appropriate amount of suitable impurity to increase the conductivity of intrinsic semiconductors$.$

• By doping with electron rich impurities, e.g., group 14 elements like Si or Ge with group 15 element like P, As etc. Free electrons become available which increase conductivity. Such solids are called n-type semiconductors.
• By doping with electron deficit impurities, e.g., group 14 element like Si or Ge with group 13 element like B, Al or Ga. As a result, holes are created. Electrons move to occupy the hopes. Thus, holes move towards negatively charges plate as if they carry positive charge. These are called p-type semiconductors.