| 摘要 |
PURPOSE:To improve the reliability of the device with an electrode wiring material layer being completely discontinued by a method wherein when a mask material is cover-attached on a semiconductor substrate to form openings for cover-attaching the electrodes, an etching is applied to form the reverse-tapered openings by using SiN as the mask material gradually increasing in etching speed as it approach to the lower layers. CONSTITUTION:An n<+> type buried layer 2 is diffused to form on a p type Si substrate 1, an n type layer 3 is epitaxially grown on the whole surface including the layer 2 and the layer 3 is separated in island-shape by a p<+> type region 4 reaching the substrate 1. Then, a p<+> type base region 5 is formed in the layer 3 made island- shape, an n<+> type emitter region 6 is formed therein and an n<+> type collector region 7 connected to the layer 2 is also diffused to form. Thereafter, to cover-attach the electrodes connected to those regions, the SiN film 14 changed in the film quality so as to be larger in the etching speed as it approaches to the lower layers is grown on an insulating film 9 having the openings 10 through the insulating film, being etched with a resist film 12 as the mask and the reversely tapered openings 13 are formed in the film 14. Thus, the Al electrodes are cover-attached in the openings 13 and put in the completely discontinued state. |
