Infrared observation of the breakdown behavior of high-voltage p-n junctions and p-n-p structures in silicon

It is shown that the radiation emitted at breakdown from large-area high-voltage p-n junctions and from p-n-p structures can be detected using an infrared image converter in conjunction with a three-stage image intensifier. In the example given, the patterns of the emitted light consist of segments of circles and spirals, indicating an inhomogeneous breakdown across the area. The inhomogeneous breakdown is attributed to resistivity striations inside the silicon. The infrared radiation emitted from the p-n-p structure was more intense by approximately one order of magnitude than that of the p-n junction, the additional emission being recombination radiation generated in front of the forward-biased emitter.