The diffusion current in p-n junction is

Question

Question

From the p-side to the n-side
From n-side to the p-side
From the n-side to the p-side if the junction is forward biased and in the opposite direction if it is reverse-biased.
From the p-side to the n-side if the junction is forward biased and in the opposite direction if it is reverse biased.

Answer 1

CONCEPT:

Diode: A diode is a two-terminal electronic component that conducts current primarily in one direction; it has low resistance in one direction, and high resistance in the other.

F1 J.K Madhu 01.07.20 D1

There are two

Forward Biasing:
- The forward bias means the positive region is connected to the p-terminal of the supply and the negative region is connected to the n-terminal of the supply.
- In forward biasing the external voltage is applied across the PN-junction diode.
Reverse Biasing:
- In reversed bias, the negative region is connected to the positive terminal of the battery, and the positive region is connected to the negative terminal.
- It creates a high resistive path in which no current flows through the circuit.

EXPLANATION:

Due to concentration differences, holes try to diffuse from the p-side to the n-side.
But the electric field at the junction exerts a force on the holes towards the left as they come to the depletion larger.
Only those holes which start moving towards the right with high kinetic energy are able to cross the junction. Similarly, diffusion of electrons takes place from right to left.
This diffusion results in an electric current from the p-side to the n-side known as diffusion current. Therefore option 1 is correct.