Manufacture of semiconductor device

Abstract

Abstract PURPOSE:To form an element isolation region with good accuracy in such a height as almost equal to the semiconductor substrate surface by selectively remaining semiconductor film within the recessed part where is become the element isolation region without depending on a pattern width of recessed part. CONSTITUTION:An SiO2 film 11, Si3N4 film 12 and PSG film 13 are formed on a P type Si substrate 10, a recessed part 15 is formed by etching, an SiO2 film 17 is formed by the thermal oxidation method, a surface layer 13a is removed by etching, a poly-Si film 18 is formed and finally heat treatment is carried out. The poly-Si film 18a, PSG film 13 are removed by etching, the poly-Si film 18 is oxidized, an SiO2 film 19 is formed. Thereafter, an element isolating region having the surface of SiO2 film 19 is formed. Thereby, difference of etching rate between the poly-Si film 18a where phosphorus is diffused and the poly-Si film 18 where phosphorus is not diffused becomes large and the poly-Si film 18 can selectively be left in the recessed part 15.

Inventors

• 👤 Kazuya Kikuchi
• 👤 菊池　和也
• 👤 Tadanaka Yoneda
• 👤 米田　忠央
• 👤 Hideaki Shimoda
• 👤 秀明 下田
• 👤 Haruhide Fuse
• 👤 玄秀 布施

Bibliographic Details