SEMICONDUCTOR DEVICE AND ITS MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a novel technique for reducing the on-voltage of a semiconductor device. SOLUTION: An insulated gate bipolar transistor comprises a semiconductor 22, a gate insulation film 36 and a gate electrode 38. The semiconductor 22 has trenches 34, and the gate insulation film 36 is formed along the wall surfaces of the trenches 34. The gate electrode 38 is formed in the trench 34. The bottom of each trench 34 is recessed to the trench 34. The semiconductor 22 has a plurality of regions 46 formed and located in the recesses. The regions 46 in the recesses are each a higher impurity concentration type region than an n--type drift region 28. COPYRIGHT: (C)2004,JPO&NCIPI