SEMICONDUCTOR DEVICE AND MANUFACTURING METHOD OF THE SAME

摘要

PROBLEM TO BE SOLVED: To prevent generation of junction leakage current and decrease in on-state current and decrease manufacturing cost.SOLUTION: A semiconductor device comprises: at least two first grooves which extend in a semiconductor substrate 1 in one direction; at least two second grooves which extend in the one direction and are provided between the two first grooves and have depths each shallower than that of the first groove; a first insulation film 8 formed on inner wall surfaces of the first and second grooves; dummy gate electrodes 12 embedded in respective first grooves; gate electrodes 11 embedded in respective second grooves; and a second insulation film in which the first and second grooves are substantially and completely buried. A top face of the dummy gate electrode 12 lies at a position deeper than a top face of the gate electrode 11.