Question

Pure silicon doped with phosphorus is:

• A. amorphous
• B. $p$-type semiconductor
• C. $n$-type semiconductor
• D. insulator

Answer 1

Answer: (C)

$n$-type semiconductor

Pure silicon doped with phosphorus is an n-type semiconductor. Silicon is tetravalent and phosphorus is pentavalent.

When silicon is doped with phosphorus, there is an excess valence electron which conducts electricity.

Hence, the correct option is $\text{C}$