| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor device capable of preventing degradation of reliability of a gate insulation film, and of coping with a finer trench pattern. SOLUTION: This MOSFET (semiconductor device) is provided with: a plurality of trenches 3 penetrating a P<SP>-</SP>type impurity region 2b; and gate electrodes 5 formed on the inside surfaces of the trenches 3 through silicon oxide films (gate insulation films) 4. The gate electrode 5 includes a polysilicon layer 5a embedded in the trench 3 to position the upper surface on the upper side relative to the P<SP>-</SP>type impurity region 2b, and facing the P<SP>-</SP>type impurity region 2b by interposing the silicon oxide film 4, and a low-resistance layer 5b formed on the upper surface of the polysilicon layer 5a, and having a small electrical resistivity relative to that of the polysilicon layer 5a. An SiN films 6 is formed between the silicon oxide films 4 and side surfaces of the low-resistance layers 5b above the P<SP>-</SP>type impurity region 2b. COPYRIGHT: (C)2009,JPO&INPIT |
