EP0502647A2
Expired / Lapsed
EP
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Conductive structure for integrated circuits
Assignee: STMicroelectronics lnc USA
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Filing: 1992-02-26
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Granted: —
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Expires: 2012-02-26
Abstract
Abstract An aluminum layer formed over a semiconductor integrated circuit. A metal layer (22) is formed over the aluminum layer (16), and both are etched to define a conductive signal line. Another metal layer (26) is deposited and etched back to form a sidewall metal regions, so that the aluminum in the conductive signal line is surrounded on the top and sides. The metallic layer used to form the sidewall regions can be selectively deposited to minimize the amount of etchback required. In the resulting structure, the metal side and top layers contain the aluminum in the signal line, and therefore help prevent problems caused by aluminum electromigration.
Inventors
- 👤 William Y. Hata
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 03:38
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/064; H10W20/40; H10W20/41; H10W20/425
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
72 words
A method for forming conductive signal lines on a semiconductor integrated circuit device, comprising the steps of: depositing a layer of a first metal material over the integrated circuit; etching the metal layer to form a signal line having sides and a top; and forming a casing of a second metal material, different form the first metal material, on the signal line, wherein the casing covers the sides of the signal line.
Claim 2
Dependent Claim
38 words
The method of Claim 1, wherein said forming step comprises: forming a top layer of a third metal material over the signal line; and forming sidewalls of the second metal material on the sides of the signal line.
Claim 3
Dependent Claim
58 words
The method of Claim 2, wherein said top layer forming step comprises the step of: before said etching step, depositing a layer of the third metal on the first metal layer, wherein the layer of third metal material is etched during said etching step to define a signal line having a top covering of the third metal material.
Claim 4
Dependent Claim
32 words
The method of Claim 2, wherein said sidewall forming step comprises the step of: selectively depositing the second metal material on the top layer and on the sides of the signal line.
Claim 5
Dependent Claim
44 words
The method of Claim 2, wherein said sidewall forming step comprises the steps of: depositing a layer of the second metal material over the device; and anisotropically etching the layer of second metal material to form sidewalls on the sides of the signal line.
Claim 6
Dependent Claim
22 words
The method of Claim 5, wherein said anisotropic etch step comprises selectively etching the second metal material over the third metal material.
Claim 7
Dependent Claim
48 words
The method of Claim 5, wherein said second metal material layer depositing step selectively deposits the second metal material on underlying conductive materials, whereby such layer has a greater thickness on exposed surfaces of the first and third metal materials than on any exposed surfaces of insulating materials.
Claim 8
Dependent Claim
85 words
A conductive element for a semiconductor integrated circuit device, comprising: an elongate element on a surface of the device, said element being formed from a first metal material and having a top and sides; a top metal layer covering the top of the elongate element, said top metal layer being formed from a metal material different from the first metal material; and metal sidewalls covering the sides of said elongate element, said sidewalls being formed from a metal material different from the first metal material.
Claim 9
Dependent Claim
35 words
The conductive element of Claim 8, wherein said top metal layer is formed form a second metal material, and wherein said sidewalls are formed from a third metal material different from the second metal material.
Claim 10
Dependent Claim
13 words
The conductive element of Claim 9, wherein said third metal material comprises tungsten.
Claim 11
Dependent Claim
28 words
The conductive element of Claim 9 or 10 where in the second metal material is suitable for functioning as an antireflective coating for the first metal material layer.
Claim 12
Dependent Claim
18 words
The conductive element of any of Claims 9 to 11, wherein the second metal material comprises titanium nitride.
Claim 13
Dependent Claim
19 words
The conductive element as claimed in any of claims 8 to 12, wherein the first metal material comprises aluminium.
References Cited (Backward Citations)
No citation records indexed.
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