Question

Which among the following elements when added to silicon forms P-type semiconductor?

• A. Sb
• B. Bi
• C. B
• D. As

Hint:

Trivalent impurities like B, Al, and Ga produce P-type semiconductors.

Answer 1

The Correct Option is C

Step 1: Understand P-type semiconductors.
P-type semiconductors are formed when a trivalent (Group 13) impurity is added to a tetravalent semiconductor like silicon. This creates holes as the majority charge carriers.
Step 2: Analyze the given options.
(A) Sb: Antimony is pentavalent and forms N-type semiconductor.
(B) Bi: Bismuth is also pentavalent and forms N-type semiconductor.
(C) B: Boron is trivalent and creates holes, hence forms P-type semiconductor.
(D) As: Arsenic is pentavalent and forms N-type semiconductor.
Step 3: Conclusion.
Boron forms P-type semiconductor when added to silicon.