Question

The width of the depletion layer of a p-n junction diode, when it is (i) forward biased and (ii) reverse biased respectively

• A. increases and increases.
• B. decreases and decreases.
• C. increases and decreases.
• D. decreases and increases.

Hint:

In a p-n junction diode, forward bias reduces the depletion region, while reverse bias increases it, affecting the current and the diode’s behavior.

Answer 1

The Correct Option is D

Step 1: Understanding the behavior of depletion region.
The width of the depletion layer in a p-n junction diode depends on the biasing conditions. - In forward bias, the width of the depletion region decreases because the external voltage reduces the barrier for charge carriers to cross the junction. - In reverse bias, the width of the depletion region increases as the applied voltage enhances the barrier, making it harder for charge carriers to cross. Step 2: Conclusion.
Thus, the width of the depletion layer decreases under forward bias and increases under reverse bias. Therefore, the correct answer is (D) decreases and increases.