SEMICONDUCTOR DEVICE AND ITS MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide an insulated gate type bipolar transistor device having a latch-up countermeasure without increasing a whole cell area, and to provide a method for manufacturing the same. SOLUTION: A semiconductor device includes a first conductive high resistance layer 11; a first conductivity type buffer layer 12 of its lower part; a second conductive base layer 13 of the upper part of the first conductive high resistance layer 11; a first conductive emitter region 15 of the upper surface of the second conductive base layer 13; an emitter electrode 16 connected to the emitter region 15; a gate electrode 18 on the channel region 17 of the second conductive base layer 13 through a silicon oxide film; a guard ring 19 deepened in the diffusion around a cell region; a second conductivity type collector layer 20 of the lower surface of the first conductive buffer layer 12 except directly under the guard ring 19; a collector electrode 22 connected to the collector layer 20; and the insulating layer 21 formed directly under the guard ring 19 or an insulating layer formed on a lower surface of the first conductivity type buffer layer. COPYRIGHT: (C)2005,JPO&NCIPI