Manufacture of semiconductor integrated circuit device

Abstract

Abstract PURPOSE:To flatten simultaneously an element isolating region and a field region by resorting to a simple process by a method wherein the formation of a field oxide film precedes the provision of a groove for the formation of an insulating region for the isolation of an element. CONSTITUTION:A nitride film 5, polycrystalline Si film 6, nitride film 7 and oxide film 8 are formed on the surface of a semiconductor substrate. Next, an opening 10 is provided in an element-forming region 23 with photoresist layers 9, 9' serving as masks. The oxide film 8 is subjected to side etching, selective oxidation is accomplished for the polycrystalline Si film 6 to be developed into an oxide film 11 to be an element region, which is followed by the removal of the films 7, 8, 11 from a portion to be developed into an element isolating groove 18. A process follows wherein the film 6 to be developed into a groove 18 is selectively oxidized for the formation of an oxide film 12, and then the substrate surface is exposed in a process wherein the films 11, 12 serves as masks. A field oxide film 15 is then formed with the films 11, 12 serving as masks. A process follows of removing the films 11, 5 from a portion planned for an element region, which is followed by the formation of a selective oxide film 17 and then of the groove 18. Finally a nitride film 20 is formed, the groove 18 is filled with a polycrystalline Si film 21, the film 21 covering the surface is removed, and then an element isolating oxide film 22 is formed on the surface of the groove 18.

Inventors

• 👤 Kenichi Suzuki
• 👤 研一 鈴木

Bibliographic Details