Question

Consider the following statements A and B and identify the correct answer:
A) germanium is preferred over silicon in the construction of Zener diode.
B) germanium has high thermal stability than silicon in the construction of Zener diode.

• A. Both (A) and (B) are true.
• B. Both (A) and (B) are false.
• C. (A) is true but (B) is false.
• D. (A) is false but (B) is true.

Answer 1

Answer: (B)

Both (A) and (B) are false.

Germanium diode does not have a sharp breakdown in reverse bias and hence, the voltage does not remain constant at $5V$ after breakdown while silicon diode is better in this respect. Hence, silicon is preferred in Zener diode. Also, thermal stability of silicon is better than germanium.