| abstract |
After formation of Cu interconnections 46 a to 46 e each to be embedded in an interconnection groove 40 of a silicon oxide film 39 by CMP and then washing, the surface of each of the silicon oxide film 39 and Cu interconnections 46 a to 46 e is treated with a reducing plasma (ammonia plasma). Then, without vacuum break, a cap film (silicon nitride film) is formed continuously. This process makes it possible to improve the dielectric breakdown resistance (reliability) of a copper interconnection formed by the damascene method. |