Table of Contents
- 1 What causes formation of depletion region in a PN junction?
- 2 When PN junction is forward biased then depletion region?
- 3 When a pn junction is formed diffusion current causes forward bias?
- 4 Why does depletion region decrease in forward bias?
- 5 When PN junction is forward biased then the depletion region is reduced and barrier height is increased?
- 6 What is depletion region in P-N junction?
- 7 Why it is called depletion region?
- 8 What is depletion region in PN diode?
What causes formation of depletion region in a PN junction?
The depletion region is caused by the diffusion of charges. The holes and the electrons diffusing towards each other combine near the junction. In doing so positive and negative ions are formed. The pair of positive and negative ions at the junction forms the dipole.
When PN junction is forward biased then depletion region?
the depletion region is reduced and barrier height is increased.
What happens to depletion layer when a forward bias is applied to a PN junction?
The forward bias voltage opposes the potential barrier. Due to this, the potential barrier is reduced and hence the depletion layer becomes thin. The conduction across p-n junction takes place due to migration of majority carriers from one region to another.
When a pn junction is formed diffusion current causes forward bias?
When a PN diode is forward biased then diffusion takes place, which will reduce the depletion width and results in the lowering of barrier potential. Hence, we can say that the diffusion current causes the barrier potential.
Why does depletion region decrease in forward bias?
In a P-N junction diode, the width of the depletion region decreases in forward bias. This is due to the electrons being attracted by the positive terminal of the battery, and hence the negative ions disappear. Thus, the forward bias narrows the depletion region, due to the carriers from the battery terminals.
What is the effect of forward bias on depletion region?
Forward bias (applying a positive voltage to the P-side with respect to the N-side) narrows the depletion region and lowers the barrier to carrier injection (shown in the figure to the right).
When PN junction is forward biased then the depletion region is reduced and barrier height is increased?
It is because the resistance of the depletion region is very high as it has no free charge carriers. In forward biasing the forward voltage opposes the potential barrier Vb. As a result of it, the potential barrier height is reduced and the width of the depletion layer decreases.
What is depletion region in P-N junction?
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.
Why does diffusion current increase in forward bias?
Overview. Forward bias occurs when a voltage is applied across the solar cell such that the electric field formed by the P-N junction is decreased. It eases carrier diffusion across the depletion region, and leads to increased diffusion current.
Why it is called depletion region?
The depletion region is so named because it is formed from a conducting region by removal of all free charge carriers, leaving none to carry a current.
What is depletion region in PN diode?
Why does depletion region decrease?
Since all the recombination process takes place at the junction or nearby region so depletion width is decreased with doping. In this manner, free electrons and holes reduce the ions. Reduction of positive ions means reduction of depletion region. Thus, the depletion region decreases.