Question

When a piece of pure silicon is doped with aluminium, then

A. The conductivity of the doped silicon piece will remain the same

B. The doped silicon piece will become n-type

C. The doped silicon piece will become p-type

D. The resistivity of the doped silicon piece will increase

Answer 1

The correct option is C) the doped silicon piece will become p-type.

p type of semiconductor is obtained when Silicon is doped with a trivalent impurity like Aluminium. Aluminium is a p-type dopant, which means that when a semiconductor i.e. silicon is doped with aluminium, it creates a hole (positively charged carrier) by accepting an electron from the silicon atom. Electrical conductivity of semiconductors increases and resistivity remains the same.