MULTILAYER INTERCONNECTION

摘要

PURPOSE:To prevent an oxide film apt to be grown on the surface of lower layer wiring from growing by a method wherein the surface of lower layer wiring is covered with a thin film made of precious metal such as Pt etc. CONSTITUTION:An impurity semiconductor region 2 comprising a semiconductor element is formed on the surface of a semiconductor substrate 1. An Al film 5 to be the main body of wiring and a thin film 6 made of precious metal such as Pt etc. covering the surface are successively deposited on the substrate 1 to form a lower layer wiring 7. Then the lower layer wiring 7 may be easily formed by means of photoetching the thin film 6 and the Al film 5. Next an interlayer insulating film 8 made of phosphorus silicate glass etc. is formed and then a throughhole is made by photoetching process. The surface of wiring 7 exposed by this throughhole but covered with the thin film 6 made of precious metal may not be corroded or formed into an oxide film. Resultantly an upper layer wiring 10 may be assured of electric conduction to the wiring 7 through the intermediary of the throughhole.