| 摘要 |
PURPOSE:To make submicron order working easy when forming an SiO2 film coated on a semiconductor substrate into a specified pattern by reducing the thickness of the film selectively by a reactive spatter etching method and removing the film by wet etching. CONSTITUTION:On a silicon substrate 1, an SiO2 film 2 is coated, and on the film, a light sensitive film 3 with an opening 4 is coated. Next, using a parallel flat plate type reactive spattering device and keeping the partial pressure ratio of CF4 and H2 at 1 to 1, the degree of vacuum at about 0.02Torr and input at about 300W, the film 2 exposed in the opening 4 is etched. At this time, the thickness of the film 2 is reduced using a dummy sample with an SiO2 film of the same thickness as that of the film 2 and confirming visually a time when the SiO2 film changes from brown to purplish red. After that, the thin film 2 remaining in the opening 4 is etched away with the solution of hydrogen fluoride and ammonium fluoride. By so doing, the amount of side etching can be reduced almost to zero and a fine pattern can be obtained. |
