| 摘要 |
A semiconductor device includes a semiconductor substrate having a surface; a plurality of spaced apart electrically insulating films disposed directly on the surface; a plurality of spaced apart electrically conducting word lines, at least one of the word lines being disposed on one of the insulating films and at least one of the word lines being disposed directly on the surface, the word lines being formed from a continuous layer of an electrically conducting material in a photolithographic process employing a photoresist film deposited on the continuous layer of electrically conducting material, the photoresist film being exposed in a single step to define masks for each of the word lines in a projection exposure apparatus including a light source for producing light; a condenser lens for condensing the light from the light source onto a mask including a circuit pattern; a projection lens having a pupil with a diameter, the projection lens for condensing the light that has passed through the mask onto a surface of a wafer; and an aperture member disposed between the light source and the condenser lens and having a transmission area with an outer diameter for shaping the light emanating from the light source and a light blocking area at a central portion of the transmission area, the outer diameter of the transmission area of the aperture member being set such that a ratio sigma of an outer diameter of an effective light source to the diameter of the pupil of the projection lens is 0.6+/-0.3 while a ratio of the light blocking area to the transmission area is 60+/-35%.
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