Interconnect with low dielectric constant insulators for semiconductor integrated circuit manufacturing
First Claim
1. A method for forming an interconnect structure on a semiconductor body, comprising the steps of:
- (a) depositing a first metal layer on a semiconductor body;
(b) depositing a sacrificial layer on the first metal layer, said sacrificial layer having a height;
(c) patterning the sacrificial layer and the first metal layer to form separate metal lines with a sacrificial layer cap on said metal lines;
(d) depositing a low-k material to fill gaps between said metal lines and to cover the sacrificial layer;
(e) removing the low-k material to a level within the height of the sacrificial layer;
(f) removing the sacrificial layer;
(g) depositing a protective layer to cover the metal lines and the low-k material (h) depositing an insulator on the protective layer;
depositing and patterning a photoresist layer on the insulator;
(i) creating vias in the insulator;
(j) performing a photoresist strip;
(k) performing a set clean; and
(l) selectively etching the protective layer using an anisotropic etch configured to leave a spacer on a vertical portion of the low-k material in the vias.
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Accused Products
Abstract
A method is provided for forming an improved interconnect structure on a semiconductor body. A first metal layer is deposited on the semiconductor body. A sacrificial layer having a height is deposited on the first metal layer. The sacrificial layer and the metal layer are patterned to form separate metal lines with the sacrificial layer remaining on said metal lines. A low-k material is then deposited to fill the gaps between metal lines and to cover the sacrificial layer. The low-k material is then removed to a level within the height of the sacrificial layer. The sacrificial layer is then removed. A protective layer is deposited on top of the metal lines and the low-k material. A dielectric layer is deposited over the protective layer. The protective layer protects the low-k material from attack by chemicals utilized by subsequent process steps to etch vias in the dielectric layer, to strip photo-resist, and to clean the vias. The protective layer is then selectively etched away to make contact between a via plug and the metal lines.
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Citations
12 Claims
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1. A method for forming an interconnect structure on a semiconductor body, comprising the steps of:
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(a) depositing a first metal layer on a semiconductor body;
(b) depositing a sacrificial layer on the first metal layer, said sacrificial layer having a height;
(c) patterning the sacrificial layer and the first metal layer to form separate metal lines with a sacrificial layer cap on said metal lines;
(d) depositing a low-k material to fill gaps between said metal lines and to cover the sacrificial layer;
(e) removing the low-k material to a level within the height of the sacrificial layer;
(f) removing the sacrificial layer;
(g) depositing a protective layer to cover the metal lines and the low-k material (h) depositing an insulator on the protective layer;
depositing and patterning a photoresist layer on the insulator;
(i) creating vias in the insulator;
(j) performing a photoresist strip;
(k) performing a set clean; and
(l) selectively etching the protective layer using an anisotropic etch configured to leave a spacer on a vertical portion of the low-k material in the vias. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
depositing a second metal layer onto the insulator and into the vias; - and
patterning and etching the second metal layer to form conductive features.
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Specification