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EP0147247A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

Method for forming hillock suppression layer in dual metal layer processing and structure formed thereby

Assignee: Monolithic Memories Inc
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Filing: 1984-06-14
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Granted: —
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Expires: 2004-06-14
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Abstract

Abstract A method is provided whereby a thin stop layer (15) of a passive metal is applied uniformly over first layer metallization (12). The thin stop layer serves as a mechanical stop against the formation of hillocks between the upper surface of the first layer metal line and overlying metal lines (13). Hillocks are thus not formed on the upper surface of the first layer metal and do not punch through the overlying dielectric regions (11) to contact second layer metallization. An additional advantage of the uniform application of the thin hillock suppression layer on the first layer metal is that an effective barrier layer is provided against the diffusion of contaminants. Furthermore, this method provides the ability to recover the wafers if an error in processing occurs after deposition and processing of the second layer of metallization.

Inventors

  • 👤 Jack D. Smith

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-01 10:10
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/40; H10W20/41; H10W20/425; H10W20/01; H10W20/031; H10W20/44; H10W20/4451

Claims Analysis

Total Claims: 17
Claim 1
Independent Claim 110 words
A method for forming a dual layer metal structure which incorporates a hillock suppression layer, comprising, providing a silicon substrate, depositing a first layer of conductive metal on said substrate, said method characterized by comprising of the steps of: applying a hillock suppression layer of a passive metal on said first layer of conduction metal; defining said hillock suppression layer to a selected pattern; defining said first layer of conductive metal; applying a layer of dielectric material over said hillock suppression layer, said first layer conduction metal and said silicon substrate; depositing a second layer of conductive material; and defining said second layer of conductive layer to a selected pattern.
Claim 2
Independent Claim 110 words
A method for forming a dual layer metal structure which incorporates a hillock suppression layer, comprising, providing a silicon substrate, depositing a first layer of conductive metal on said substrate, said method characterized by comprising of the steps of: applying a hillock suppression layer of a passive metal on said first layer of conduction metal; defining said hillock suppression layer to a selected pattern; defining said first layer of conductive metal; applying a layer of dielectric material over said hillock suppression layer, said first layer conduction metal and said silicon substrate; depositing a second layer of conductive material; and defining said second layer of conductive layer to a selected pattern.
Claim 3
Dependent Claim 33 words
The method as in Claim 1 further characterized in that said passive metal comprises a material selected from the group of materials consisting of titanium, tungsten, platinum, nickel, chromium, gold, silver and silicon.
Claim 4
Dependent Claim 31 words
The method as in Claim 1 further characterized in that said passive metal comprises a material selected from the group of materials consisting of titanium silicide, tungsten silicide, and platinum silicide.
Claim 5
Dependent Claim 31 words
The method as in Claim 1 further characterized in that said first layer of conductive metal comprises a material selected from the group of materials consisting of aluminum and polycrystalline silicon.
Claim 6
Dependent Claim 31 words
The method as in Claim 1 further characterized in that said second layer of conductive metal comprises a material selected from the group of materials consisting of aluminum and polycrystalline silicon.
Claim 7
Dependent Claim 31 words
The method as in Claim 1 which is further characterized by including the steps of providing an insulating layer on said silicon substrate and beneath said first layer of conductive metal.
Claim 8
Dependent Claim 25 words
The method as in Claim 6 which is further characterized by including the step of providing an additional hillock suppression layer on said dielectric layer.
Claim 9
Dependent Claim 30 words
The method as in Claim 6 further characterized in that said insulating material comprises a material selected from the group of materials consisting of oxides of silicon and silicon nitride.
Claim 10
Dependent Claim 30 words
The method as in Claim 1 further characterized in that said insulating material comprises a material selected from the group of materials consisting of oxides of silicon and silicon nitride.
Claim 11
Dependent Claim 46 words
1 0. A semiconductor structure comprising a substrate, a first metal layer, said structure characterized by comprising a hillock suppression layer coextensive with said first metal layer; a dielectric layer formed over said hillock suppression layer; and a second metal layer formed over said dielectric layer.
Claim 12
Dependent Claim 46 words
1 0. A semiconductor structure comprising a substrate, a first metal layer, said structure characterized by comprising a hillock suppression layer coextensive with said first metal layer; a dielectric layer formed over said hillock suppression layer; and a second metal layer formed over said dielectric layer.
Claim 13
Dependent Claim 34 words
The structure as in Claim 10 further characterized in that said hillock suppression layer comprises a material selected from the group of materials consisting of titanium, tungsten, platinum, nickel, chromium, gold, silver and silicon.
Claim 14
Dependent Claim 32 words
The structure as in Claim 10 further characterized in that said hillock suppression layer comprises a material selected from the group of materials consisting of titanium silicide, tungsten silicide, and platinum silicide.
Claim 15
Dependent Claim 29 words
The structure as in Claim 10 further characterized in that said first metal layer comprises a material selected from the group of materials consisting of aluminum and polycrystalline silicon.
Claim 16
Dependent Claim 29 words
The structures as in Claim 10 further characterized in that said second metal layer comprises a material selected from the group of materials consisting of aluminum and polycrystalline silicon.
Claim 17
Dependent Claim 30 words
The structure as in Claim 10 further characterized in that said dielectric layer comprises a material selected from the group of materials consisting of oxides of silicon and silicon nitride.

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