| 摘要 |
PURPOSE:To form a flat oxide film by a method wherein a substrate is selectively oxidized using the first Si3N4 film as a mask, the first Si3N4 film and a selected oxide film are removed, and the substrate is selectively oxidized secondly using the second Si3N4 film as a mask when forming the selected oxide film of the semiconductor device. CONSTITUTION:The first mask 2 in Si3N4 is made up on the Si substrate 1, the substrate is selectively oxidized, and an SiO2 film 3 is built up. The first nitrided film 2 is removed while all oxide film 3 is taken away by means of etching. The second nitrided film mask 4 is formed on the surface of the Si substrate, and an SiO2 film is patterned according to a selective oxidizing pattern. The substrate is selectively oxidized secondly, and an SiO2 film 5 is made up. Thus, the disconnection and cracks of electric wiring can be removed because the selected oxide film for an extremely flat field film can be formed. |
