| 摘要 |
<p>In this semiconductor device, a trench gate MOS structure is provided on one main surface side of a semiconductor substrate, said one main surface side to be an n- drift region (1a). In the n- drift region (1a), an n shell region (13) in contact with the n- drift region (1a)-side of a p base region (2a) is provided, said p base region constituting the trench gate MOS structure. The n shell region (13) has impurity concentration higher than that of the n- drift region (1a). The effective dose quantity of the n type impurity in the n shell region (13) is 5.0×1012 cm-2 or less. The n- drift region (1a) has resistivity with which, at the time when a backward rated voltage is applied with an emitter as a positive electrode, a depletion layer extending from a p collector region (10a) on the other main surface side does not reach the n shell region (13) or the bottom portion of a first trench (5), which is closer to the p collector region (10a) than the other.</p> |
