Question

The process of adding impurities to a pure semiconductor is called
1. Mixing
2. Diffusing
3. Doping
4. None of the above

Answer 1

Correct Answer - Option 3 : Doping

The process of adding impurities is called doping.

An extrinsic semiconductor is of 2 types:

n-type:

• When the trivalent impurity is added to an intrinsic or pure semiconductor (silicon or germanium), then it is said to be a p-type semiconductor.
• Trivalent impurities such as Boron (B), Gallium (G), Indium (In), Aluminum (Al), etc are called acceptor impurity.

 

p-type:

• When a pentavalent impurity is added to an intrinsic or pure semiconductor (silicon or germanium), then it is said to be an n-type semiconductor.
• Pentavalent impurities such as phosphorus (P), arsenic (As), antimony (Sb), etc are called donor impurity.