Semiconductor device and method for manufacturing the same
View Patent ↗The present invention provides a semiconductor device having a multilayer wiring structure including a lower Cu buried-wiring layer, a SiC film, a SiOC film of 400 nm in thickness functioning as an interlayer insulating film, and an upper Cu buried-wiring layer electrically connected to the lower buried-wiring layer through contact plugs passing through the interlayer insulating film. The contact plugs and the upper Cu buried wiring layer are formed a single burying step of the dual damascene process. The SiOC film has a carbon content of about 12 atomic % and a relative dielectric constant of about 3.0. The upper Cu buried wiring layer is formed by burying a Cu film, through a barrier metal, in wiring grooves which are provided in the inter-wiring insulating film including a laminated film of an organic film, e.g., a PAE film of 200 nm in thickness, and a SiOC film of 150 nm in thickness.
1. A semiconductor device having a wiring structure formed by a dual damascene method, the wiring structure comprising:
a lower buried-wiring layer;
an interlayer insulating film provided on the lower buried-wiring layer;
an inter-wiring insulating film provided on the interlayer insulating film; and
an upper buried-wiring layer buried in wiring grooves provided in the inter-wiring insulating film, the upper buried-wiring layer being electrically connected to the lower buried- wiring layer through contact plugs passing through the interlayer insulating film;
wherein the interlayer insulating film is a first carbon-containing silicon oxide film (SiOC film); and
the inter-wiring insulating film comprises a laminated insulating film including an organic low dielectric constant insulating film, and a multi-layer second carbon-containing silicon oxide film provided on the low dielectric constant insulating film and having a plurality of layers with different carbon contents, the carbon content of the top layer of the second carbon-containing silicon oxide film being lower than that of the first carbon-containing silicon oxide film.
2. The semiconductor device according to claim 1 , wherein the carbon content of the top layer of the second carbon-containing silicon oxide films is 3 atomic % to 9 atomic %.
3. The semiconductor device according to claim 1 , wherein the lower buried-wiring layer is buried in an inter-wiring insulating film provided below the interlayer insulating film and comprising an organic insulating film and a carbon-containing silicon oxide film provided on the organic insulating film.