| 摘要 |
PURPOSE:To prevent a disconnection by a method wherein a U-shaped part for interconnection use is filled uniformly, another insulating layer is formed on a substratum which has been made flat by eliminating the difference in level between an interconnection and an insulating layer and an interconnection formed on it is set to a uniform thickness which is not influenced by the shape of a first-layer interconnection and the interval between interconnections. CONSTITUTION:First-layer tungsten interconnections 9a to 9d are grown and formed up to the height of insulating layers 7a to 7c on exposed titanium nitride films 6a to 6d by a tungsten selective CVD method. U-shaped parts 8a to 8d for interconnection use are filled. Then, an Si oxide film is grown, by a CVD method, on the first-layer tungsten interconnections 9a to 9d which have been made flat by filling the U-shaped parts 8a to 8d and on the insulating layers 7a to 7c. An insulating layer 10 is formed. Since the first-layer interconnections 9a to 9d and the insulating layers 7a to 7d which are used as the substratum of the insulating layer are formed to be flat without any difference in level, the insulating layer formed on them becomes flat over the whole surface. Lastly, Al is deposited on the whole surface of the flat insulating layer 10. It is etched and removed selectively by a photoetching operation. Second-layer interconnections 11a to 11c are formed. |
