Semiconductor device having insulating layers containing oxygen and a barrier layer containing manganese

Abstract

A semiconductor device includes an insulating layer formed over a semiconductor substrate, the insulating layer including oxygen, a first wire formed in the insulating layer, and a second wire formed in the insulating layer over the first wire and containing manganese, oxygen, and copper, the second wire having a projection portion formed in the insulating layer and extending downwardly but spaced apart from the first wire.

What is claimed is: 
     
         1 . A semiconductor device comprising:
 an insulating layer formed over a semiconductor substrate, the insulating layer containing oxygen;   a wire formed in the insulating layer, the wire containing copper;   a structure formed in the wire, the structure containing oxygen; and   an oxide layer formed between the wire and the structure, or between the wire and the insulating layer, the oxide layer containing manganese.   
     
     
         2 . The semiconductor device according to  claim 1 , wherein the structure has a grooved shape. 
     
     
         3 . The semiconductor device according to  claim 1 , wherein the structure substantially includes the same substance as the insulating layer. 
     
     
         4 . A method of manufacturing a semiconductor device comprising:
 forming a first insulating layer over a semiconductor substrate, the insulating layer containing oxygen;   forming a first wire in the first insulating layer;   forming a second insulating layer over the first insulating layer and the first wire, the second insulating layer containing oxygen;   selectively removing the second insulating layer to form a first groove over the first insulating layer;   selectively removing the second insulating layer on the inner wall of the first groove to form a first opening exposing the first wire formed under the first groove, and a second opening extending downwardly but spaced apart from the first wire;   forming a first metal layer over the inner wall of the first groove, the first opening and the second opening, the first metal layer containing manganese;   forming a second metal layer in the first groove, the first opening and the second opening, the second metal layer containing copper; and   performing a heat treatment to form a barrier layer between the second metal layer and the second insulating layer, the barrier layer containing manganese oxide.