In semiconductors at a room temperature

Options

A. the valence band is completely filled and the conduction band is partially filled
B. the valence band is completely filled
C. the conduction band is completely empty
D. the valence band is partially empty and the conduction band is partially filled

Answer

D

Explanation

In a semiconductor conduction and valence bands are separated by a small energy gap called forbidden energy gap (`E_g` ). At room temperature, some electrons from the V band acquire thermal energy(`E_"Th"`). lf `E_"Th" gt E_g`, they go to the conduction band and holes are created in the V band. Thus at room temperature, C-band is partially filled and V band is partially empty. This is option (d).