| 摘要 |
PURPOSE:To obtain inter layer insulating films having few fear of disconnection and short-circuiting and have a superior water-tightness by a method wherein CVD-SiO2 films are put upon Si3N4 films formed on PSG films. CONSTITUTION:A source, drain or gate electrode 4 and a wiring layer 5, etc., are prepared, openings 10-12 are formed selectvely in PSG9 and Si3N4 20, SiO2 13 are laminated on them. Openings 14-16 are formed in the SiO2 13, but the PSG9 does not etched as the Si3N4 20 acts as a stopper. Then openings are formed in the Si3N4 20, and Al wirings 17-19 are formed selectively. By this method, as the PSG9 dose not gouged by etching, the disconnection in the wiring 19 does not take place. As two-layer film of Si3N4 and SiO2 is laid on the PSG9, it displays the sufficient water-proof effect, the withstanding voltage is elevated by the existence of Si3N4 film and a multilayer wiring structure having a highly reliable inter layer insulating film can be obtained. |
