| 摘要 |
PURPOSE:To make a wiring connecting hole small by a method wherein, when a wiring connecting hole is to be formed on an insulating film consisting of an SiO2 film and a PSG film on a semiconductor substrate, firstly only the PSG film is etched to diffuse the impurities into the SiO2 film thus exposed and then the SiO2 film is etched to form the wiring connecting hole. CONSTITUTION:A semiconductor substrate, wherefrom the photoresistance 4 in the position where a wiring connecting hole is required to be formed, is removed, is etched to firstly etch a PSG film 2 only. Next, the photoresistance 4 is totally exfoliated to change the SiO2 film exposed being diffused with phosphor by means of thermal diffusion into the SiO2 film converted into PSG. Subsequently being etched again, the wiring connecting hole is formed on the SiO2 film changed into PSG. Thereby the etching is performed in a shorter time as compared with the SiO2 film 1 thus to reduce the horizontal extension of the wiring connecting hole of the PSG film. |
