Question
The impurity atoms with which pure silicon may be doped to make it a p-type semiconductor are those of:
  1. Phosphorus.
  2. Boron.
  3. Antimony.
  4. Aluminium.

Answer

  1. Boron.

  1. Aluminium.

Explanation:

A p-type semiconductor is formed by doping an intrinsic semiconductor with a trivalent atom (atom having valency 3). As phosphorous and boron have three valence electrons, they can be doped with silicon to make a p-type semiconductor.

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