A NUMERICAL-ANALYSIS OF TRANSIENT CHARGE PARTITIONING

The rigorous numerical analysis of charge partitioning in a simple p-n junction structure is presented. Procedures for extracting the releva nt terminal charges, based upon the concept of a ''pass-through'' curr ent, are introduced. The calculation of the pass-through current, the electrostatic displacement current and the (distinct) current associat ed with the changes in internal charge distributions are described. Me thods for dividing the various internal charges into ''quasineutral'' and ''space-charge'' components, are also presented. The results obtai ned by exact analysis are compared with the predictions of the convent ional, analytic, charge partitioning models. Significant discrepancies are found to arise from the simplifications necessary for analytic mo deling such as the dependence of the partitioning on the ramp speed an d injection level and asymmetry between switch-on and switch-off trans ients. The numerical simulation results offer guidance for the future development of alternative, more accurate, nonquasi-static device mode ls.