| 摘要 |
PURPOSE:To prevent wirings from disconnecting due to an overhang by isotropically etching an interlayer insulating film from the hole of a resist mask and then anisotropically etching to increase the inner diameter of the uppermost portion of the hole larger than that of the lower portion. CONSTITUTION:A P type layer 2 is provided on an N type Si substrate 1, a resist mask 4 is superposed on an SiO2 film 3, the surface of the film 3 is isotropically etched at 10 in the degree of 5-15% of the thickness of the film 3 with diluted fluoric acid from a hole 9 on the layer 2 to form an overhang 11. Then, it is anisotropically ethced by parallel plate plasma etching to complete a through hole 12, the mask 4 is removed, and aluminum wirings 7 are coated. According to this configuration, since no overhang of the interlayer film is not provided in the connecting hole, no disconnection occurs at the metal wiring layer. |
