Explain forward bias and reverse bias briefly along with the graph - Physics - Semiconductor Electronics Materials Devices And Simple Circuits

Question

Explain forward bias and reverse bias briefly along with the graph

Aditi · Accepted Answer

p-n junction diode under forward bias

p-side is connected to positive terminal and n-side to the negative terminal Applied voltage drops across the depletion region Direction of applied voltage (V) is opposite to the build in potential (V0) As the depletion layer width decreases, the barrier height is reduced Effective barrier height under forward bias is (V0 − V)

Electron in n-region moves towards the p-n junction and holes in p-region move towards the junction The width of the depletion layer decreases and hence, it offers less resistance Diffusion of majority carriers takes place across the junction This leads to forward current p-n junction diode under reverse bias

Positive terminal of battery is connected to n-side and negative terminal to p-side Reverse bias supports the potential barrier Therefore, the barrier height increases and the width of depletion region also increases Effective barrier height under reverse bias is (V0 + V)

No conduction across the junction due to majority carriers; few minority carriers cross the junction after being accelerated by high reverse bias voltage This constitutes a current that flows in opposite direction − celled reverse current