SEMICONDUCTOR DEVICE AND ITS MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a semiconductor device of an insulating gate type, wherein an electric power loss upon a turn-off is restrained, whereas an on voltage is reduced between a collector and an emitter. SOLUTION: An n-type first base layer 2 is formed on a semiconductor substrate 1 having a first main face and second main face, and a p-type second base layer 3 is formed on its upper layer. A carrier storing layer 4 is formed between the first base layer 2 and the second base layer 3. The carrier storing layer 4 has a high concentration impurity layer 4a and a low concentration impurity layer 4b. The high concentration impurity layer 4a has a thickness of 1.5μm or more, and an impurity concentration of this layer is set to 1.0×1016cm-3or more throughout the entire layer. COPYRIGHT: (C)2008,JPO&INPIT