Describe the mechanism of doping intrinsic semiconductor to obtain p-type semiconductor ?

Doping is the process of intentionally introducing impurities into a semiconductor material in order to modify its electrical properties. In the case of an intrinsic semiconductor, which is a pure semiconductor material with no intentional impurities, doping can be used to create either p-type or n-type semiconductors.

To create a p-type semiconductor, a small amount of a trivalent impurity is added to the intrinsic semiconductor material. Trivalent impurities have three valence electrons, such as boron or aluminum. When these impurities are added to the semiconductor material, they replace some of the host atoms in the crystal lattice.

The trivalent impurity atoms have one less valence electron than the host atoms, creating "holes" in the crystal lattice where an electron is missing. These holes act as positive charge carriers in the material, leading to an excess of positive charge carriers and creating a p-type semiconductor.

The addition of trivalent impurities increases the hole concentration in the material, making it easier for electrons to move around and increasing the overall conductivity of the semiconductor. This results in a p-type semiconductor with a predominance of positive charge carriers (holes) and a lower electron concentration compared to the intrinsic semiconductor.

Overall, doping an intrinsic semiconductor with trivalent impurities creates a p-type semiconductor by introducing positive charge carriers (holes) into the material, which can be used in various electronic devices such as diodes and transistors.