Question

In extrinsic P and N type semiconductor materials, the ratio of the impurity atom to the pure semiconductor atoms is about

(a) 1 (b) \( 10^{-1} \) (c) \( 10^{-4} \) (d) \( 10^{-7} \)

Answer 1

The correct option is (D) 10^-7.

The ratio of the pure atoms to impure atoms in extrinsic semiconductors is 10⁻⁷. When pure or intrinsic semiconductors are doped with trivalent or pentavalent impurities then it results in the formation of n-type and p-type semiconductors.

This drastically affects the conduction of these semiconductors and provides free charge carriers to conduct electricity through the crystal.