Question

What happens when a forward bias is applied to a p-n junction?

Answer 1

In forward biasing, the applied voltage mostly drops across the depletion region, and the voltage drop across the p-side and n-side of the junction is negligible. The direction of the applied voltage(V) is opposite to the built-in potential$V_o$as a result, the depletion layer width decreases and the barrier height is reduced. The effective barrier height under forward bias is $(V_o-V)$