| 摘要 |
PURPOSE: To obtain best degree of integration by completely preventing a short circuit between a metal and a gate resulting from over-etching by combining anisotropic etching, so as to form a steep sidewall in the bottom section of an interlayer insulator layer and isotropic etching so as to form an inclined sidewall in an upper section. CONSTITUTION: An insulating layer film consisting of a phosphoric-acid glass first layer 232 and a second layer 236 holding an Si3 N4 intermediate layer is formed onto integrated-circuit compositions 200, 202, 204, 210, 220 with transistors, the second layer 236 is etched in an isotropic manner by hydrofluoric acid, while using a resist film having opening sections at the places of specified contact holes as a mask, and anisotropic etching penetrated through the Si3 N4 layer and the first layers 232/230 is performed by plasma. The Si3 N4 layer functions as an etch stopper to isotropic etching, the contact holes are formed into a Y-shape, when isotropic etching and anisotropic etching are combined and reducing the aspect ratios, and a short circuit due to over-etching can be prevented completely. |
