Question

Applying forward bias to p-n junction, the potential barrier ______.

• A. increases.
• B. decreases.
• C. remains unchanged.
• D. becomes zero.

Hint:

Forward Bias $\rightarrow$ Pushes holes and electrons TOWARD the junction $\rightarrow$ Shrinks the depletion region $\rightarrow$ Decreases potential barrier $\rightarrow$ Current flows easily! Reverse bias does the exact opposite.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
In forward bias, the positive terminal of the battery is connected to the p-type and the negative to the n-type. This opposes the built-in potential of the depletion layer.

Step 2: Formula Application:
Effective Barrier Potential $V_{eff} = V_B - V_{forward}$.

Step 3: Explanation:
The applied voltage pushes majority carriers toward the junction, narrowing the depletion region and lowering the height of the potential barrier.

Step 4: Final Answer:
The potential barrier decreases.