Interconnection structure of semiconductor integrated circuit device

Abstract

A semiconductor integrated circuit device has an interconnection structure in which multilayer aluminum interconnection layers are connected through a connection hole. A first aluminum interconnection layer is formed on a main surface of said semiconductor substrate. An insulating layer is formed on the first aluminum interconnection layer and has a through hole extending to a surface of the first aluminum interconnection layer. A second aluminum interconnection layer is formed on the insulating layer and is electrically connected to the first aluminum interconnection layer through the through hole. The second aluminum interconnection layer includes a titanium layer, a titanium nitride layer and an aluminum alloy layer. The titanium layer is formed on the insulating layer to be in contact with the surface of the first aluminum interconnection layer through the through hole. The titanium nitride layer is formed on the titanium layer. The aluminum alloy layer is formed on the titanium nitride layer. An electrical contact resistance between the first and second aluminum interconnection layers is stabilized, and resistance against the electron-migration and stress-migration is improved in the interconnection structure.

Dependencies are inferred from the claim text.