How do you calculate depletion region?

How do you calculate depletion region?

Depletion approximation: the electric field is confined to the junction region and there is no electric field in the quasi-neutral regions. No free carriers (n(x), p(x) = 0 ) in depletion region. 1 q d J n d x = ( U − G ) = 0 . This means that Jn is constant across the depletion region.

How do you find the potential barrier of a diode?

Definition: The potential barrier in the PN-junction diode is the barrier in which the charge requires additional force for crossing the region. In other words, the barrier in which the charge carrier stopped by the obstructive force is known as the potential barrier.

What is built-in potential formula?

Built-in Potential also known as buil-in voltage is defined as the potential difference or electric field between acceptor and donor concentration is dropped across the depletion region of PN junction diode or semiconductor device in thermal equilibrium due to electrons diffusing across the junction.

What do you mean by built-in potential?

Equilibrium (zero bias) In a p–n junction, without an external applied voltage, an equilibrium condition is reached in which a potential difference forms across the junction. This potential difference is called built-in potential .

Is there an electric field in the depletion region?

Depletion approximation: the electric field is confined to the junction region and there is no electric field in the quasi-neutral regions. No free carriers ( n (x), p (x) = 0 ) in depletion region. We can assume no free carriers since the electric field sweeps them out of the depletion region quickly.

How to find a solution for the depletion region?

Major assumptions: depletion approximation, no free carriers in this region, dopant concentration is constant. Based on these assumptions, can use Poisson’s Equation to develop a solution for the depletion region. Can solve for both the maximum electric field and the total depletion width.

Is the net charge of the depletion region equal?

In other words, if the electric field is confined to the depletion region, then the net charge in Region II must be zero, and hence the negative charge and the positive charge must be equal.

Which is the depletion region of the p-n junction?

We call this region the depletion region, extending from x = – xp to x = xn. The charge due to the ionized donors and acceptors causes an electric field, which in turn causes a drift of carriers in the opposite direction.