Ncert Exercises & Solutions

A perfect crystal of silicon is doped with some elements as given in the options. Which of these options shows n-type semiconductors?

a. b.

c. d.

1. (a, b)

2. (b, c)

3. (c, d)

4. (a, c)

Hint: Group 15 elements like P or As occupy some of the lattice sites in silicon or germanium crystal

n-type semiconductor When group 15 elements are doped into a perfect crystal it leads to the formation of an n-type semiconductor.

Here, in (a) as (group 15, period 3) is doped to perfect Si-crystal and in (c) as (group 15, period 2) is doped to perfect Si-crystal.