ENHANCEMENT EFFECT OF THE DEMBER FIELD IN FORWARD SEMICONDUCTOR p+–n JUNCTIONS

Taking account of ambipolar diffusion and drift in long-base silicon p+–n junctions under low-level injection conditions, a developed analytical model for the total drift field enhanced by the Dember field with different mobilities is presented in excellent agreement with numerical simulation results. Based on the results of theoretical analysis and numerical simulation, the entire current in the n-type quasineutral region is found to consist of minority-hole diffusion-component and majority-electron drift- and diffusion-component and the Dember field plays a dominant role in modulating the local drift field to balance all components above to keep the current continuity. Our analytical model provides a comprehensive interpretation of ambipolar current character to fully understand existing theories of semiconductor devices.