Calculation of depletion layer thickness by including the mobile carriers

A useful analytical approximation for depletion layer thickness, which takes into account the effect of mobile carriers under high forward bias is presented. The new expression predicts, in agreement with computer simulations, a significantly smaller depletion layer thickness at high forward bias than that of conventional theory. The results of these effects for heterojunctions shows a less pronounced effect. The model's validity for different forward biases is also illustrated. Finally, the effect of temperature dependence is discussed.