SOLUTION

Recombination in semiconductors refers to the annihilation of holes and electrons.

Detailed Explanation

⇒ In an intrinsic semiconductor, electrons and holes are produced continuously on account of thermal agitation.

⇒ Since the electrons and holes move in the crystal in a random manner, there is a possibility of an electron meets a hole.

⇒ The merging of a free electron and a hole is called recombination.

⇒ Recombination in semiconductors refers to the annihilation of holes and electrons.

⇒ At any temperature, the rate of this recombination is equal to the rate of generation of electrons and holes.

⇒  However, an electron for a holed travels some distance before it recombines.

⇒ The average time an electron (or hole) remains free is called its lifetime.