Avalanche breakdown voltage of multiple epitaxial pn junctions

Calculation of the peak electric field at breakdown for two-sided step junctions with arbitrary doping levels on each side is presented. The theoretical predictions are compared with the results of experimental breakdown studies of a series of carefully prepared and characterized high voltage diodes. Calculations based upon the ionization coefficients determined by Van Overstraeten and De Man are shown to be in better agreement with experiment than those based on the ionization coefficients of Lee et al.