| 摘要 |
A hard Al oxide film having a high melting point, which grows on the surface of an Al-Cu film during a wafer is carried in atmospheric air, obstructs the burying of a viahole with the Al-Cu film by high pressure reflow, with a result that a void remains in the hole. The present invention is intended to remove such an Al oxide film grown on the Al-Cu film formed by sputtering, by Ar+ sputtering/etching directly before high pressure reflow. Moreover, when a Ti oxide film is present on the surface of a Ti based underlying film formed by CVD, an Al oxide film is possibly grown at the boundary between the Ti based underlying film and an Al-Cu film laminated thereon. In this case, the Ti oxide film is similarly removed directly before formation of the Al-Cu film, thereby preventing the growth of the Al oxide film. With this method, it is possible to highly keep thermal flow of a conductive film in a high pressure reflow process, and hence to desirably bury a connection hole with the conductive film.
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