PURPOSE: To lessen the capacity between an conductive region and the protrusion of a gate electrode.

CONSTITUTION: In case that the top of a gate electrode 60 has a protrusion 62, the first insulating film 72 shorter than the length of the protrusion in the longitudinal direction of a gate is provided all over the surface of the gate electrode by anisotropic stacking method. The second insulating film 74 is provided on this first insulating film from the direction vertical to a board by anisotropic stacking. At this time, a gap 84 is formed below the protrusion. The third continuous insulating film 76 without a break is made on this second insulating film by anisotropic stacking method. A gate protective film is made of these first, second, and third insulating films. As a result, a gate protective film, where a gap in the width direction of a gate is left below the protrusion, is gotten.