Method of manufacturing a high-reliability semiconductor device

Abstract

A semiconductor device is provided, which includes a substrate, an insulator film formed over the substrate, and plural metal wirings with different widths containing copper as a main component and an impurity which is different from copper. The plural metal wirings includes a first metal wiring having a concentration profile where the concentration of the impurity metal increases from the center part of the stacking direction to the surface and the second metal wiring having a concentration profile where the concentration of the impurity metal decreases from the bottom surface of the stacking direction to the surface. Moreover, the width of the second metal wiring may be larger than the width of the first metal wiring.

1 . A manufacturing method of a semiconductor device comprising:
 forming a wiring metal in a plurality of grooves with different widths formed in an insulator film which is formed over a substrate,   wherein forming the wiring metal includes:   forming a first seed alloy film containing copper and an impurity metal which is different from copper by using a sputtering method to embed a part of the grooves;   planarizing the film thickness of the first seed alloy film at the side wall of the grooves by etching the first seed alloy film;   forming a second seed alloy film containing copper and the impurity metal by using a sputtering method over the first seed alloy film to embed a part of the grooves;   forming a plated metal layer containing copper as a main component over the second seed alloy film to embed the other part of the grooves; and   annealing the first seed alloy film, the second seed alloy film, and the plated metal film.   
     
     
         2 . The manufacturing method of a semiconductor device according to  claim 1 ,
 wherein an overhung portion is formed on the second seed alloy film in forming the second seed alloy film.   
     
     
         3 . The manufacturing method of a semiconductor device according to  claim 1 ,
 wherein the grooves include a first groove and a second groove which is wider than the first groove, and   wherein forming the wiring metal is performed on in the first groove and the second groove, respectively.   
     
     
         4 . The manufacturing method of a semiconductor device according to  claim 3 ,
 wherein the first groove is a groove for forming the minimum wiring pitch in the semiconductor device, and   wherein the second groove is a groove for forming the maximum wiring in the semiconductor device.