In a reverse biased p-n junction, when the applied bias voltages is equal to the breakdown voltage, then

Options

A. Current remains constant while voltage increase sharply
B. Voltage remains constant while current increases sharply
C. Current and voltage increase
D. Current and voltage decrease

Answer

### Step-by-Step Solution:

1. **Understanding Reverse Biasing**:
- In a reverse-biased p-n junction diode, the p-region is connected to the negative terminal of the power supply and the n-region is connected to the positive terminal. This configuration increases the potential barrier at the junction.

2. **Formation of Potential Barrier**:
- When reverse bias is applied, the potential barrier at the junction increases, preventing the flow of majority carriers (holes in p-type and electrons in n-type) across the junction.

3. **Behavior Near Breakdown Voltage**:
- As the reverse voltage is increased, the current remains very low until a certain critical voltage is reached, known as the breakdown voltage. At this point, the diode can no longer maintain the low current.

4. **Breakdown Mechanism**:
- When the applied reverse voltage reaches the breakdown voltage, the electric field across the junction becomes strong enough to cause a phenomenon known as avalanche breakdown. This results in the generation of a large number of minority charge carriers (electrons in p-type and holes in n-type).

5. **Current Increase**:
- At breakdown voltage, the current through the diode increases sharply. This happens because the newly generated minority carriers contribute to the current flow, leading to a rapid increase in reverse current.

6. **Voltage Behavior**:
- Despite the increase in current, the voltage across the diode remains approximately constant at the breakdown voltage. This is because the diode has entered a breakdown region where it can conduct a large amount of current without a significant increase in voltage.

7. **Conclusion**:
- Therefore, in a reverse-biased p-n junction when the applied bias voltage is equal to the breakdown voltage, the voltage remains constant while the current increases sharply.

### Final Answer:
In a reverse-biased p-n junction, when the applied bias voltage is equal to the breakdown voltage, the voltage remains constant while the current increases sharply.