How is depletion region of a diode affected by reverse bias condition?
A reverse bias reinforces the potential barrier and impedes the flow of charge carriers. The depletion layer of a diode is substantially thinner while in forward bias and much thicker when in reverse bias. Forward bias decreases a diode’s resistance, and reverse bias increases a diode’s resistance.
What is bias of pn junction?
Bias. A diode (PN junction) in an electrical circuit allows current to flow more easily in one direction than another. Forward biasing means putting a voltage across a diode that allows current to flow easily, while reverse biasing means putting a voltage across a diode in the opposite direction.
What is pn junction diode define depletion region?
Depletion region or depletion layer is a region in a P-N junction diode where no mobile charge carriers are present. Depletion layer acts like a barrier that opposes the flow of electrons from n-side and holes from p-side.
When is the PN junction diode under forward bias?
When the PN junction diode is under forward bias condition, the p-type is connected to the positive terminal while the n-type is connected to the negative terminal of the external voltage. When the diode is arranged in this manner, there is a reduction in the potential barrier.
How is the pnjunction biased in an external circuit?
The pnjunction can be biased by connecting to an external circuit and there are two types of biasing (similar to the arguments for the metal-semiconductor Schottky junction) 1.Forward bias 2.Reverse bias 1 MM5017: Electronic materials, devices, and fabrication Figure 1: pnjunction under (a) equilibrium, (b) forward and (c) reverse bias.
What happens to depletion width in forward bias?
The depletion width shrinks in forward bias and expands in reverse bias. Adapted from Semiconductor device physics and design – Umesh Mishra and Jasprit Singh.
Why does a PN junction lead to a current?
This leads to a lowering of the barrier for injection of electrons from the nto the pside (there is a similar lowering of the barrier for holes to be injected from pto nside) and leads to a current in the circuit. This current is due to the injection of minority carriers in the pnjunction.