| 摘要 |
PURPOSE:To improve integration density by comprising element isolating region consisting of a first silicon oxide film, silicon nitride film and second, third silicon oxide films. CONSTITUTION:A photo resist film 12 is selectively provided at the surface of P type silicon substrate 11. With this photo resist film 12 used as a mask, the substrate 11 is etched in order to form ?-shaped groove 13. A photo-resist film 12 is removed, a silicon oxide film 15 is provided, a silicon nitride film 16 is provided in the thickness of several thousands of Angstrom on such silicon oxide film 15 and a poly-silicon film 17 is formed thereon. Then, a silicon film 18 is formed on th poly-silicon film 17. The silica film 18 is changed to a third silicon oxide film 20 and simultaneously the poly-silicon film 17 is also changed to a silicon oxide film 19. Finally, an element isolation region is completed by selectively removing the first, second, third silicon oxide films 15, 19, 20 and the silicon nitride film 16 excpet for the element isolation region by the etching using photo resist. |
