Question

Discuss the effect of external voltage on the width of depletion region of a p-n junction.? ​

Answer 1

Answer:

The external voltage is inversely proportional to width of depletion that is if voltage increases width decreases

Answer 2

The effect of external voltage on the width of the depletion layer in a diode would depend upon whether the diode is forward biased or reverse biased.

1) In case of forward bias, there is recombination of the P type and N type majority carriers in the junction.

2) Here, the width of the depletion region decreases. This happens because the applied voltage decreases the voltage drop as compared to the voltage which was previously present in the p-n junction.

3) In case of reverse bias, the P type majority carriers i.e holes move away from the junction as they are attracted towards the negative terminal and the N type majority carriers i.e electrons move away from the junction as they are attracted by the positive terminal. This leads to increase in the thickness of the depletion layer.