Question

A P-type semiconductor can be obtained by adding
(a) Arsenic to pure silicon
(b) Gallium to pure silicon
(c) Antimony to pure germanium
(d) Phosphorous to pure germanium

Answer 1

A large number of holes are provided in the semiconductor material by the addition of trivalent impurities like Gallium and Indium. Such type of impurities which produces p-type semiconductor are known as an Acceptor Impurities because each atom of them create one hole which can accept one electron.
Energy Band Gap of p-Type Semiconductor and
Conduction through p-Type Semiconductor,

Answer 2

Answer:(b) gallium to pure silicon

Explanation:p type semiconductor have trivalent impurity.so it have holes as majority charge carrier .In above option only gallium is trivalent element.