Patent ID: 7211837
Filing Date: 2007-05-01
Classification: H01L

Abstract:
1. An insulated gate semiconductor device comprising: a first conductivity type first base region; a second conductivity type collector region formed on a lower main face of the first conductivity type first base region; a collector electrode connected to the collector region; a second conductivity type second base region selectively formed on an upper main face of the first conductivity type first base region; a first conductivity type carrier stored layer formed between the second base region and the first base region and having an impurity concentration higher than that of the second base region; a first conductivity type emitter region selectively formed in the second base region; a trench selectively formed in the second base region and having a depth reaching inside of the first conductivity type first base region; a gate electrode buried in the trench through an insulation film; and an emitter electrode connected to both the second base region and the emitter region, wherein the second base region located in the periphery of the gate electrode functions as a channel region, and when it is assumed that an impurity concentration of a first carrier stored layer region located just under the channel region is ND