Question

$10^{16}$ phosphorus atoms $c{m}^{-3}$ and $2\times 10^{16}$ boron atoms $c{m}^{-3}$ are doped in a sample of silicon. If all the dopants are fully ionised, the material is

• A. n-type with carrier concentration of $3\times 10^{16}c{m}^{-3}$ .
• B. p-type with carrier concentration of $10^{16}c{m}^{-3}$ .
• C. p-type with carrier concentration of $3\times 10^{16}c{m}^{-3}$ .
• D. intrinsic.

Answer 1

Answer: (B)

Boron is trivalent impurity and phosphorus is pentavalent impurity. Here majority charge carriers are holes.