Control of current-mode second breakdown in transistors through use of double-graded collectors

Abstract

Bipolor transistors with double-graded collectors offer the prospect of achieving a substantial measure of protection against device failure from current-mode second breakdown, which cannot be achieved from a uniformly doped epitaxial transistor where the scope for improvement is fundamentally limited by a need to support the required blocking voltage. Optimal values of double-graded collector parameters of transistors are numerically computed, and empirical expressions for optimal parameters are found.