US 7,115,517 B2 · Method of fabricating a dual damascene interconnect structure

Abstract

A method of fabricating an interconnect structure (e.g., dual damascene interconnect structure, and the like) of an integrated circuit device is disclosed. The interconnect structure is fabricated using a bi-layer mask comprising an imaging film and an organic planarizing film. The bi-layer mask is used to remove lithographic misalignment between a contact hole, a trench, and an underlying conductive line when the interconnect structure is formed. Additionally, a sacrificial layer may be used to protect an inter-metal dielectric (IMD) layer during subsequent planarization of the interconnect structure. The sacrificial layer may be formed of amorphous silicon (Si), titanium nitride (TiN), tungsten (W), and the like. The interconnect structure may be formed of a metal (e.g., copper (Cu), aluminum (Al), tantalum (Ti), tungsten (W), titanium (Ti), and the like) or a conductive compound (e.g., tantalum nitride (TaN), titanium nitride (TiN), tungsten nitride (WN), and the like).

Claims21

Dependent claims

A method of fabricating an interconnect structure, comprising:

(a) providing a substrate having a film stack formed thereon;
(b) patterning and etching a first feature in the film stack, wherein the first feature is a trench etched in the film stack to a pre-determined depth;
(c) forming a bi-layer mask comprising an organic film and an imaging film on the film stack;
(d) patterning the bi-layer mask;
(e) etching a second feature in the film stack using the patterned bi-layer mask as an etch mask, wherein the second feature is a contact hole, and wherein a portion of the organic film in the trench is used as an etch mask so as to remove lithographic misalignment between the contact hole and the trench when the contact hole is etched;
and
(f) metallizing the first and second features to form the interconnect structure.

4 more elements

Dependencies are inferred from the claim text.

Method of fabricating a dual damascene interconnect structure

Life of this patent

Method of fabricating a dual damascene interconnect structure

Life of this patent

Abstract

Claims21