MHT CET Medical202621 April 2026Evening ShiftPhysicsSemiconductorsActual
In semiconductors, at room temperature
Options
- Athe valence band is completely empty.
- Bthe conduction band is completely empty.
- CThe valence band is partially empty and the conduction band is partially filled.
- Dthe valence band is completely filled and the conduction band is partially filled.
Correct answer
C. The valence band is partially empty and the conduction band is partially filled.
Step-by-step solution
At 0 K , the valence band of a semiconductor is completely filled and the conduction band is completely empty. At room temperature, some electrons in the valence band acquire sufficient thermal energy to jump across the forbidden energy gap into the conduction band. This transition leaves behind vacant energy states (holes) in the valence band. Thus, at room temperature, the valence band becomes partially empty and the conduction band becomes partially filled. Answer: The valence band is partially empty and the con