INSULATING GATE BIPOLAR TRANSISTOR

摘要

Fluctuation of switching characteristics of an insulating gate bipolar transistor (IGBT) having an NPT (Non Punch Through) structure is suppressed. In the IGBT, in a region (A) not covered with an interlayer insulating film (9) in a region between trenches (2, 2) adjacent to each other, a P type base region (4) and an N+ type emitter region (7) are formed, and a PN junction composed of an N- type drift layer (3) and a base layer (4) is formed. In a region (B) covered with the interlayer insulating film (9), since the base region (4) is not formed, an PN junction is not formed. Thus, in the region (B), floating state of the base region (4) is not generated.