Abstract: A sidewall insulating film (11) made of a silicon oxide film is formed on the sidewall of a gate electrode (7) (word line) with an aim to reduce the capacitance to the word line serving as the major component of the bit line capacitance. Also, when openings for connecting the bit lines are formed above the spaces of the gate electrodes (7) (word lines) by the dry etching of a silicon oxide film (31) above contact holes (12), a silicon nitride film (19) to be an etching stopper is provided below the silicon oxide film (31) so as to reduce the amount of the bottom surface of the opening receded below the upper surface of a cap insulating film (9).

Abstract: A sidewall insulating film (11) made of a silicon oxide film is formed on the sidewall of a gate electrode (7) (word line) with an aim to reduce the capacitance to the word line serving as the major component of the bit line capacitance. Also, when openings for connecting the bit lines are formed above the spaces of the gate electrodes (7) (word lines) by the dry etching of a silicon oxide film (31) above contact holes (12), a silicon nitride film (19) to be an etching stopper is provided below the silicon oxide film (31) so as to reduce the amount of the bottom surface of the opening receded below the upper surface of a cap insulating film (9). A side-wall insulating film (11) composed of a silicon oxide film is formed on the side wall of a gate electrode (7) (word line WL) to reduce pair word line capacity components as a main component of a bit line capacity.