| 摘要 |
PURPOSE:To completely remove a damaged layer produced by ion etching by carrying out a reactive ion etching on the surface of a semiconductor substrate, and then oxidizing or wet etching at least more than 100Angstrom on the surface. CONSTITUTION:An SiO2 film 2 of approx. 100Angstrom thick and an Si3N4 film 3 of approx. 1,000Angstrom thick are laminated on an Si substrate 1, a resist mask 4 is covered on an element forming region, is etched with reactive ions to remove the expose film 3 and then the film 3, and the field region of the substrate is exposed. Then, the surface of the exposed region 5 is removed at least in the amount of more than 100Angstrom by wet etching with aqueous alkaline solution or low temperature oxidiation including steam under higher than 9 atms at lower than 700Angstrom , or anodic oxidiation, thereby removing the damaged layer, and a field oxidized film 6 is formed thereon. In this manner, the corner 3'' of the remaining film 3 almost becomes vertical, and the length of bird beak introduced between the films 2 and 3 at the end of the film 5 constructed therewith can be extremely reduced. |
