摘要 |
In a method of smoothing the edges of a window through a PSG film of a semiconductor device, a masking film is provided under the PSG film, so as to prevent impurities of the PSG film from penetrating into semiconductor substrate during the heating of the PSG film for the smoothing of the edges. A masking film, for example, an Si3N4 film, does not, however, inhibit the penetration of hydrogen gas, which can improve the properties of an MIS semiconductor device. |