The p+n−n+ diode pulsed at extreme current densities—I: Numerical techniques and reverse pulsed case

The anomalous voltage transient response of the p⁺n^?n⁺ diode structure to a single non-repetitive intense current pulse is presented for current densities up to and greater than 10⁴ amp/cm². A very general device model and an accurate numerical iterative method are used to solve the basic transport equations leaving the selection of pulse wave form, generation-recombination laws, avalanching, doping profiles, mobility, and injection levels arbitrary. The boundary conditions are applied solely to the external contacts. In order to achieve numerical convergence to such a nonlinear problem, due to the extreme currents, it was determined that a very accurate thermal equilibrium solution was necessary. Two examples for the reverse pulse case, reach-through and avalanche, are presented to show the effects of large current densities on the reverse voltage response.