Q: With which one of the following elements silicon should be doped so as to give p-type of semiconductor ?

Explanation:

P-type Semiconductor

To create a p-type semiconductor, silicon is doped with an element that has one fewer valence electron than silicon. Silicon has four valence electrons, so an element with three valence electrons is ideal for p-type doping.

Boron is a Group III element, which means it has three valence electrons. When boron is introduced into the silicon lattice, it creates “holes” or positive charge carriers because there are not enough electrons to complete the bonds. These holes can move through the silicon structure, allowing electrical current to flow. This process effectively creates a p-type semiconductor, where the majority charge carriers are holes.

The other elements listed do not serve this purpose:
– Germanium is also a Group IV element, like silicon, and does not introduce holes.
– Arsenic and selenium are Group V and Group VI elements, respectively, which have five and six valence electrons. When they are used to dope silicon, they add extra electrons, creating an n-type semiconductor instead of a p-type.

Therefore, boron is the appropriate choice for doping silicon to achieve a p-type semiconductor.