| 摘要 |
<P>PROBLEM TO BE SOLVED: To shorten a wafer processing step of a reverse blocking IGBT having a step of forming a p-type isolation trench which has an inclined trench in the rear surface and is connected conductively with a p-type collector layer. <P>SOLUTION: The method of manufacturing a reverse blocking IGBT comprises: a step of forming a p-type region 20 at a position surrounding a device region on the surface of an n-type wafer 1; a step of forming an MOS gate structure 10 and an Al electrode 18 in the device region; a step of coating a resist 22b as a protective film of the surface; a step of forming an etching mask of a photoresist 22a at a position facing the device region on the rear surface of the wafer 30; a step of forming an inclined trench 23 reaching the bottom of the p-type region 20 from the rear surface by alkali etching; a step of removing only the photoresist 22a on the rear surface by an organic alkaline stripping solution; and a step of forming an isolation layer 4b along the inclined trench 23 while forming a p-type collector layer 6 on the rear surface by ion implantation and annealing. <P>COPYRIGHT: (C)2012,JPO&INPIT |
