Patent ID: 7238609

Claim:
A method for fabricating a semiconductor device, the method comprising the steps of: forming a conductive film on a specified region of a substrate; forming an insulating film on the substrate such that the conductive film is covered with the insulating film; forming, on the insulating film, a mask layer having a first opening pattern above the conductive film; performing first etching with respect to the insulating film by using the mask layer having the first opening pattern to form, in the insulating film, a depressed portion having a bottom portion not reaching the conductive film; forming a mask layer having a second opening pattern having an opening diameter larger than an opening diameter of the first opening pattern by enlarging the opening diameter of the first opening pattern; performing second etching with respect to the insulating film by using the mask layer having the second opening pattern to form, in the insulating film, an opening for exposing the conductive film; and forming, at least in the opening a capacitor element composed of a lower electrode, a capacitor insulating film, and an upper electrode, wherein a diameter of the opening increases gradually from the bottom portion toward the top portion, and wherein the step of forming the capacitor element includes the steps of: forming the lower electrode such that the wall surface of the opening and the bottom surface of the opening are covered with the lower electrode; forming the capacitor insulating film on the lower electrode; and forming the upper electrode on the capacitor insulating film.