Question

Current through a reverse biased p-n junction, increases abruptly at

• A. \(0.0\) V
• B. \(0.8\) V
• C. break-down voltage.
• D. knee voltage.

Hint:

The reverse current rises sharply when the reverse voltage reaches the breakdown value.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept
Under reverse bias only a tiny, nearly constant reverse saturation current flows, carried by minority carriers.

Step 2: What happens at high reverse voltage
When the reverse voltage reaches a critical value, the strong electric field breaks covalent bonds (Zener effect) or causes carriers to knock out more carriers (avalanche). The current then rises sharply.

Step 3: Conclusion
This critical voltage is the break-down voltage. The knee voltage belongs to forward bias.

Final Answer:
The reverse current increases abruptly at the break-down voltage. \[ \boxed{\text{(C) }\text{break-down voltage}} \]