Abstract
A versatile computer program that includes the basic electronic and thermal processes important in second breakdown is described. Calculations of static and dynamic voltage-current characteristics showed that with increasing current density, regions of single-avalanthe, space-charge-limited, double-avalanche, and negative-differential-resistance current flow can be identified. Analytic expressions for the static characteristic in the three positive resistance regions are presented for several diodes at a few temperatures. Second breakdown voltages of more than double the first breakdown voltage have been computed.