SEMICONDUCTOR DEVICE

PROBLEM TO BE SOLVED: To provide a semiconductor device that allows improving the current driving capability of a RCAT.SOLUTION: A semiconductor substrate 11 has gate grooves 13. A diffusion layer 12 is formed on a surface region of the semiconductor substrate 11 corresponding to upper portions of the gate grooves 13. Gate insulating films 14 are formed on wall surfaces of the gate grooves. Gate electrodes 15 are formed inside and outside the gate grooves 13. A film 16 having compressive stress is formed on the entire surfaces of the gate electrodes 15 outside the gate grooves 13.