| 摘要 |
PURPOSE:To simplify the process of forming alignment marks for an electron beam exposure and reduce a man-hour required to manufacture a semiconductor device by a method wherein, after a buried insulative film is formed, the film is removed partially until a substrate is exposed by etching to form recessed parts on the substrate. CONSTITUTION:A buried layer 2 is formed in, and an Si epitaxial layer 3 is formed on a substrate 1. After an SiO2 film 4 is formed, a silicon nitride film is formed. A photoresist film of a prescribed pattern is formed and an Si3N4 film 5 patterned into a prescribed form is formed by etching using the photoresist film as a mask. Then the substrate 1 is subjected to heat-oxidization to form an SiO2 film 6 for element isolation using the Si3N4 film 5 as a mask. Then a photoresist film 7 is applied and prescribed apertures are made. The SiO2 films 6A at the apertures are removed by etching. Recessed parts 8 formed like this are used as alignment marks for an electron beam exposure. |
