Multilevel interconnect structure
AssigneeKawasaki Steel Corporation
InventorsHiroshi Yamamoto, Tomohiro Ohta, Nobuyuki Takeyasu
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Abstract
A multilevel interconnect structure for use in a semiconductor device includes a lower metal wiring having an aluminum or aluminum alloy film and a high melting point metal or high melting point metal alloy film. An interlayer insulating film is deposited on the lower metal wiring and a via hole is formed in the interlayer insulating film. A plug made of aluminum or aluminum alloy is formed in the via hole. An upper metal wiring has an aluminum or aluminum alloy film and a high melting point metal or high melting point metal alloy film. The plug directly contacts the aluminum or aluminum alloy film of at least one of the lower and upper metal wirings to decrease the via resistance without reducing the electromigration reliability.
Claims92
A multilevel interconnect structure formed on a surface of a substrate of a semiconductor device comprising:
- a lower metal wiring including one of an aluminum and an aluminum alloy film;
- an upper metal wiring including one of an aluminum and an aluminum alloy film;
- an interlayer insulating film formed between said lower and upper metal wirings such that the lower and upper metal wirings are electrically isolated from each other by said interlayer insulating film;
- a via hole formed in said interlayer insulating film such that the lower and upper metal wirings are communicated with each other by said via hole;
- and
- a plug made of one of aluminum and an aluminum alloy and formed in said via hole such that upper and lower ends of the plug contact the upper and lower metal wirings, respectively;
- wherein
- at least one of said lower and upper metal wirings further comprises one of a high melting point metal and a high melting point metal alloy film;
- and
- said plug contacts said at least one of the lower and upper metal wirings which comprises one of the high melting point metal and the high melting point metal alloy film by means of an interface including one of aluminum-aluminum, aluminum-aluminum alloy, and aluminum alloy-aluminum alloy.
Dependencies are inferred from the claim text.