| 摘要 |
PURPOSE:To form an element isolating region of flat and infinitesimal width without heat treatment of high temperature and long time by utilizing a lift-off technique. CONSTITUTION:A silicon oxide film 2 is grown on a P type silicon substrate 1, and a silicon nitride film 3 is accumulated thereon. Then, with a photoresist film as a mask the film 3 is selectively removed, and the film 2 is further overetched. Thereafter, exposed silicon substrate is etched to form a groove 6, and a silicon thermal oxide film 7 is formed on the inner surface thereof. Subsequently, an SiO2 film is accumulated on the whole surface, and an SiO2 film 81 on the film 3 and an SiO2 film 82 in the groove 6 are discontinused and isolated. Then, the film 3 is removed to lift off the film 81, and an element isolating region 9 is formed. Thus, the element isolating region having high flatness can be formed. |
