What is the importance of energy gap in a semiconductor?

1.	What is the importance of energy gap in a semiconductor?
Answer» 1. The gap between the bottom of the conduction band and the top of the valence band is called the energy gap or the band gap. 2. This band gap is present only in semiconductors and insulators. 3. Magnitude of the band gap plays a very important role in the electronic properties of a solid. 4. Band gap in semiconductors is of the order of 1 eV. 5. If electrons in valence band of a semiconductor are provided with energy more than band gap energy (in the form of thermal energy or electrical energy), then the electrons get excited and occupy energy levels in conduction band. These electrons can easily take part in conduction.

Answer»

1. The gap between the bottom of the conduction band and the top of the valence band is called the energy gap or the band gap.

2. This band gap is present only in semiconductors and insulators.

3. Magnitude of the band gap plays a very important role in the electronic properties of a solid.

4. Band gap in semiconductors is of the order of 1 eV.

5. If electrons in valence band of a semiconductor are provided with energy more than band gap energy (in the form of thermal energy or electrical energy), then the electrons get excited and occupy energy levels in conduction band. These electrons can easily take part in conduction.

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