Question

In the context of p-n junction, select the correct statement from the following: (A) The barrier potential remains constant under forward bias

• A. The width of the depletion region depends on the doping level
• B. Under forward bias, it behaves like a pure resistor
• C. Under reverse bias, it behaves like a pure resistor
• D. The barrier potential decreases under reverse bias
• E.

Hint:

Higher doping ⇒ thinner depletion layer ⇒ easier conduction.

Answer 1

The Correct Option is B

Concept: Depletion region is formed due to diffusion of carriers and is strongly affected by doping.

Step 1: Effect of doping \[ W \propto \frac{1}{\sqrt{\text{doping concentration}}} \]
• Heavy doping → narrow depletion region
• Light doping → wide depletion region

Step 2: Bias behavior
• Forward bias → decreases barrier potential
• Reverse bias → increases barrier potential \[ \boxed{\text{Depletion width depends on doping}} \]