What are semiconductors? Name any two semiconductors.

Explanation

### Step-by-Step Solution:

1. **Definition of Semiconductors**:
- Semiconductors are materials that have electrical conductivity between that of conductors and insulators. This property arises due to their energy band structure, specifically the energy band gap (EG) between the valence band and the conduction band.

2. **Energy Band Gap**:
- For a material to be classified as a semiconductor, the energy band gap (EG) must be less than 3 electron volts (eV). This relatively small band gap allows electrons to jump from the valence band to the conduction band under certain conditions, such as temperature increase or impurity doping.

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