Patent ID: 8507327

Claim:
A method for manufacturing a semiconductor device, comprising the steps of: forming a second conductive type first region on a surface layer of a first principal plane of a wafer and in an outer periphery portion of a semiconductor device formed on the wafer; forming grooves which reach the first region with a dicing blade from a second principal plane to the first principal plane of the wafer; removing processing strain formed on the grooves by etching; forming a second conductive type isolation layer on a surface layer of the grooves and a second conductive type collector layer on a surface layer of the second principal plane so that the isolation layer and the collector layer are connected; forming a collector electrode on the collector layer; and cutting into chips the wafer in the first region sandwiched between the first principal plane and each bottom portion of the grooves approximately vertically with respect to the first principal plane by dicing or by laser.