Question

Which of the following dopant is NOT used in Ge to obtain n-type semiconductor?

• A. P
• B. As
• C. Sb
• D. B

Hint:

N-type doping uses group 15 elements with five valence electrons, while boron gives a p-type semiconductor.

Answer 1

The Correct Option is D

Step 1: Recall the doping rule.
Group 15 dopant in group 14 host: extra electron, n-type. Group 13 dopant: electron deficiency, p-type.

Step 2: Sort the four.
P, As, Sb belong to group 15. B belongs to group 13.

Step 3: Decide.
Boron gives holes, so it is the dopant that is NOT used for n-type Ge.

Final Answer:
Option (D). \[ \boxed{\text{B}} \]