| 摘要 |
PURPOSE:To enable the formation of a contact window having a high dielectric strength by a method wherein an indent around a first conductor pattern having an oxidation-resisting mask film is filled up with an etching mask layer and an exposed portion of the oxidation-resisting mask is removed selectively with said etching mask layer as a mask. CONSTITUTION:A substrate is spin-coated with an etching mask layer, e.g. a resist film 23, being thick enough to fill up an indent located between gates. Next, the resist film 23 is removed by etching from the top so that an Si3N4 film 22 is exposed, and indents 24a, 24b, 234c, 24d and 234e located between gate electrodes are filled up selectively with the resist film 23. Next, the resist film 23 in the indents being used as a mask, the Si3N4 film 22 exposed on gate electrodes 4a, 4b, 4c and 4d and ion the top of an SiO2 lower-layer insulating film 7 located on the side of said gate electrodes is removed selectively by dry etching, and thereby a polycrystalline silicon layer 21 in a region is exposed selectively. Then, thermal oxidation is applied with the Si3N film 22 used as a mask, and thereby an SiO2 film 25 is formed selectively on the exposed surface of the polycrystalline silicon layer 21. |
