Manufacture of semiconductor device

Abstract

Abstract PURPOSE:To enable to simultaneously form the grooves having different depths to be used for isolation by a method wherein, when an interelement isolation proccess is performed on a bipolar integrated circuit, the film growing characteristics in a chemical vapor-phase growing method are utilized. CONSTITUTION:A PSG film 13 is grown to the thickness of several 1,000Angstrom -1mum by performing a CVD method in accordance with patterning. As the thickness of the film 13 is more than one half of the width of the aperture of the narrow isolation groove, the narrow part of the width of the aperture can be filled up by the film growing characteristics of the CVD method, and the wide width part of the aperture is not filled up, because the thickness of the film 13 is less than one half of the opening width of the groove. After an etching has been performed in the thickness of the film 13 on the whole surface of the film 13, a V-shaped isolation groove is formed in a suitable depth, wherein the groove will not reach an n<+> type buried layer for example, by performing an anisotropic etching using KOH. At this time, the narrow part of the opening is filled up with the film 13, and no groove is formed there. Lastly, after the film 13 remaining at the narrow part of the opening has been removed, a U-shaped groove Vs is formed at the narrow part, and a deep groove Vi is formed at the wide part by performing a reactive ion etching.

Inventors

• 👤 Hiroshi Goto
• 👤 広志 後藤
• 👤 Ryoji Abe
• 👤 良司 阿部

Bibliographic Details