Some experiments of secondary breakdown in forward and reverse bias conditions

New understandings are suggested concerning the mechanism of secondary breakdown of transistor, measured by different structural double diffused silicon transistors. After approximately one tenth of BVCEO was applied to the testing transistor by the constant voltage source, increasing the base current to flow the collector current sufficiently in order to enter into the secondary breakdown, the trigger current of the secondary breakdown IM is proportional rather to the emitter area than the emitter to base periphery length.