Air-Gap Formation in Interconnect Structures
AssigneeTaiwan Semiconductor Manufacturing Company, Ltd.
InventorsCheng-Hsiung Tsai, Chung-Ju Lee, Tien-I Bao
Life of this patent
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Abstract
A structure includes a substrate, and a first metal line and a second metal line over the substrate, with a space therebetween. A first air gap is on a sidewall of the first metal line and in the space, wherein an edge of the first metal line is exposed to the first air gap. A second air gap is on a sidewall of the second metal line and in the space, wherein an edge of the second metal line is exposed to the second air gap. A dielectric material is disposed in the space and between the first and the second air gaps.
Claims22
A structure comprising:
- a substrate;
- a first metal line and a second metal line over the substrate, with a space therebetween;
- a first air gap on a sidewall of the first metal line and in the space, wherein an edge of the first metal line is exposed to the first air gap, with the edge of the first metal line being a vertical straight edge, and wherein the first air gap has a tapered profile, with lower widths of an upper portion of the first air gap increasingly greater than upper widths of the upper portion of the first air;
- a second air gap on a sidewall of the second metal line and in the space, wherein an edge of the second metal line is exposed to the second air gap;
- and
- a dielectric material comprising a lower portion in the space and between the first and the second air gaps.
(canceled)
A structure comprising:
- a substrate;
- a first metal line over the substrate, wherein the first metal line comprises:
- a copper-containing line;
- and
- a dielectric barrier layer comprising a top portion over and contacting the first metal line, and an edge portion contacting a sidewall of the first metal line;
- a first air gap encircling the first metal line, wherein the edge portion of the dielectric barrier layer comprises an edge exposed to the first air gap;
- and
- a low-k dielectric region comprising a lower portion, wherein the lower portion comprises a sidewall exposed to the first air gap, and wherein the sidewall of the lower portion of the low-k dielectric region is more curved than the edge of the edge portion of the dielectric barrier layer.
15-20. (canceled)
A structure comprising:
- a substrate;
- a first low-k dielectric layer over the substrate;
- a conductive barrier comprising:
- a first portion over and contacting a top surface of the low-k dielectric layer;
- and
- a second portion extending into the low-k dielectric layer, wherein the second portion comprises sidewall portions on sidewalls of the first low-k dielectric layer;
- a via between the sidewall portions of the conductive barrier;
- a first metal line over and connected to the via, wherein edges of the first metal line are aligned to edges of the first portion of the conductive barrier;
- a dielectric barrier layer comprising a top portion over and contacting the first metal line, and edge portions contacting opposite sidewalls of the first metal line;
- and
- a first air gap encircling the first metal line, wherein the edge portions of the dielectric barrier layer are exposed to the first air gap.
Dependencies are inferred from the claim text.