Question

For $p$ -type semiconductor, choose the correct option:

• A. The number of electrons in conduction band is more
  than the number of holes in valence band at room
  temperature.
• B. The number of holes in valance band is more than
  the number of electrons in conduction band at room
  temperature.
• C. There are no holes and electrons at room temperature.
• D. The number ofholes and electrons is equal in valence
  and conduction band at room temperature.

Answer 1

Answer: (B)

In $p$ -type semiconductor,holes are the majority charge carriers and electrons are the minority charge carriers.

Increasing the energy of holes is equivalent to promoting electron from the valence band into the acceptor levels.this creates holes in the valence band that are free to propagate in the direction of an electric field.such a semiconductor is called a $p$ -type semiconductor becuse the charege carriers are positive.