Explain what is doping.

1.	Explain what is doping.
Answer» 1. The process of adding impurities to an intrinsic semiconductor is called doping. 2. The impurity atoms are called dopants which may be either trivalent or pentavalent. The parent atoms are called hosts. 3. The dopant material is so selected that it does not disturb the crystal structure of the host. 4. The size and the electronic configuration of the dopant should be compatible with that of the host. 5. Doping is expressed in ppm (parts per million), i.e., one impurity atom per one million atoms of the host. 6. Doping significantly increases the concentration of charge carriers.

Answer»

1. The process of adding impurities to an intrinsic semiconductor is called doping.

2. The impurity atoms are called dopants which may be either trivalent or pentavalent. The parent atoms are called hosts.

3. The dopant material is so selected that it does not disturb the crystal structure of the host.

4. The size and the electronic configuration of the dopant should be compatible with that of the host.

5. Doping is expressed in ppm (parts per million), i.e., one impurity atom per one million atoms of the host.

6. Doping significantly increases the concentration of charge carriers.

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