Breakdown walkout in planar p-n junctions

Department of Electrical Engineering, Stanford University, Stanford, CA 94305, U.S.A.
Solid-State Electronics (Impact Factor: 1.5). 06/1978; 21(6):813-819. DOI: 10.1016/0038-1101(78)90305-2


Junction breakdown walkout in p-n junctions has been investigated in this paper. It has been shown that walkout is closely related to the avalanching in the junction. During the time the junction is subjected to the reverse breakdown, because of avalanching, hot electrons are generated in the depletion region. Some of the hot electrons have enough energy to cross the oxide-silicon barrier and to go into the conduction band of the oxide. The electrons are trapped in the traps and charge the oxide negatively, resulting in reduction of electric field intensity in the surface depletion region of the p-n junction. This results in an increase of the breakdown voltage. A theory has been developed to explain hot electron injection and trapping in the oxide and its effect on the breakdown voltage. A comparison of results predicted by theory, with the experiments has also been carried out.

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