Bidirectional power switch with optimized emitter spacing near control electrode

摘要

A semiconductor device comprises first to third semiconductor layers of P, N and P conductivity types, first and second emitter regions of an N conductivity type, with predetermined patterns, these emitter regions being formed in the first and third semiconductor layers, and an auxiliary emitter region of an N conductivity type, which region is formed in the third semiconductor layer. The first and second emitter regions are so arranged as to have overlapping portions and a separating portion, these portions being located close to the gate region, as viewed in the laying direction of the layers.