Question

The diffused impurities with ___ valence electrons are called donor atoms.

Answer 1

The diffused impurities with 5 valence electrons are called donor atoms. For example, an atom of column V of the periodic table, such as phosphorus, arsenic, or antimony, substituting for a regular atom of a germanium or silicon crystal is a donor because it has one or more valence electrons which can be detached and added to the conduction band of the crystal.