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Low dielectric constant insulation layer for integrated circuit structure and method of making same

Assignee: LSI Corp
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Filing: 1994-02-04
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Granted: 1996-02-27
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Expires: 2014-02-04
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Abstract

Abstract A low dielectric constant insulation layer for an integrated circuit structure material, and a method of making same. The low dielectric constant insulation layer comprises a porous insulation layer, preferably sandwiched between non-porous upper and lower insulation layers. The porous insulation layer is formed by depositing a composite layer comprising an insulation material or a material which can be converted to an insulation material, by a converting process and a material which can be converted to a gas upon subjection to the converting process. Release of the gas leaves behind a porous matrix of the insulation material which has a lower dielectric constant than the composite layer.

Inventors

  • 👤 Ashok K. Kapoor

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 19:23
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/60; H10P14/69; H10P14/6903; H10P14/6905; H10P14/63; H10P14/6326; H10P14/6328; H10P14/6334; H10P14/65; H10P14/6502; H10P14/6506; H10P14/6516; H10P14/6518; H10P14/6519; H10P14/6529; H10P14/6548; H10W; H10W20/00; H10W20/01; H10W20/071; H10W20/072; H10W20/074; H10W20/075; H10W20/40; H10W20/45; H10W20/46; H10P14/6336; H10P14/66; H10P14/665; H10P14/668; H10P14/6681; H10P14/6682; H10P14/692; H10P14/6921; H10P14/6922; Y; Y10; Y10S; Y10S148/00; Y10S148/081

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 164 words
A process for forming a low dielectric constant insulation layer on an integrated circuit structure on a semiconductor wafer which comprises: a) forming a composite layer comprising one or more materials which are convertible to a gas and one or more materials which either are themselves insulation materials or are convertible to insulation materials; and b) converting said composite layer to a porous low dielectric constant insulation layer, wherein: said step of forming said composite layer on said semiconductor wafer further comprises depositing said composite layer on said wafer by a chemical vapor deposition process; said step of forming said composite layer further comprises depositing on said semiconductor wafer a mixture comprising: a) polycrystalline silicon, comprising the material which is convertible to an insulation material; and b) carbon, comprising the material which is convertible to a gas; and said step of converting said composite layer comprises simultaneously oxidizing said polycrystalline silicon to form silicon dioxide and oxidizing said carbon to produce gaseous carbon dioxide.
Claim 2
Dependent Claim 164 words
A process for forming a low dielectric constant insulation layer on an integrated circuit structure on a semiconductor wafer which comprises: a) forming a composite layer comprising one or more materials which are convertible to a gas and one or more materials which either are themselves insulation materials or are convertible to insulation materials; and b) converting said composite layer to a porous low dielectric constant insulation layer, wherein: said step of forming said composite layer on said semiconductor wafer further comprises depositing said composite layer on said wafer by a chemical vapor deposition process; said step of forming said composite layer further comprises depositing on said semiconductor wafer a mixture comprising: a) polycrystalline silicon, comprising the material which is convertible to an insulation material; and b) carbon, comprising the material which is convertible to a gas; and said step of converting said composite layer comprises simultaneously oxidizing said polycrystalline silicon to form silicon dioxide and oxidizing said carbon to produce gaseous carbon dioxide.
Claim 3
Dependent Claim 41 words
The process of claim 1 wherein one or more materials which either are themselves insulation materials or are convertible to insulation materials comprise about 10 wt % to about 90 wt % of said composite layer prior to said converting step.
Claim 4
Dependent Claim 26 words
The process of claim 1 wherein said step of forming said composite layer further comprises forming said composite layer with one or more optional dopants present.
Claim 5
Dependent Claim 23 words
The process of claim 1 including the further step of heating said composite layer to planarize said layer prior to said converting step.
Claim 6
Dependent Claim 86 words
The process of claim 1 including the further steps of: a) forming one or more lower non-porous insulation layers on said integrated circuit structure prior to said step of forming said composite layer, to thereby prevent downward migration of impurities from said porous structure into said integrated circuit structure; and b) forming one or more upper non-porous insulation layers over said low dielectric constant insulation layer after said converting step to thereby prevent upward migration of impurities from said porous structure into said integrated circuit structure.
Claim 7
Dependent Claim 39 words
The process of claim 1 wherein said step of forming said composite layer on said semiconductor wafer by a chemical vapor deposition process further comprises depositing said composite layer while maintaining a plasma during said chemical vapor deposition process.
Claim 8
Dependent Claim 69 words
The process of claim 5 including the further steps of: a) forming one or more contact openings in said one or more lower non-porous insulation layers, said low dielectric constant insulation layer, and said one or more upper non-porous insulation layers; b) filling said contact openings with conductive material; and c) forming a patterned metal layer over an upper surface of said one or more upper non-porous insulation layers.
Claim 9
Dependent Claim 164 words
A process for forming a low dielectric constant insulation layer on an integrated circuit structure on a semiconductor wafer which comprises: a) forming a composite layer comprising one or more materials which are convertible to a gas and one or more materials which either are themselves insulation materials or are convertible to insulation materials; and b) converting said composite layer to a porous low dielectric constant insulation layer, wherein: said step of forming said composite layer on said semiconductor wafer further comprises depositing said composite layer on said wafer by a chemical vapor deposition process; said step of forming said composite layer further comprises depositing on said semiconductor wafer a mixture comprising: a) polycrystalline silicon, comprising the material which is convertible to an insulation material; and b) germanium, comprising the material which is convertible to a gas; and said step of converting said composite layer comprises simultaneously oxidizing said polycrystalline silicon to form silicon dioxide and oxidizing said carbon to produce gaseous germanium nitride.
Claim 10
Dependent Claim 164 words
A process for forming a low dielectric constant insulation layer on an integrated circuit structure on a semiconductor wafer which comprises: a) forming a composite layer comprising one or more materials which are convertible to a gas and one or more materials which either are themselves insulation materials or are convertible to insulation materials; and b) converting said composite layer to a porous low dielectric constant insulation layer, wherein: said step of forming said composite layer on said semiconductor wafer further comprises depositing said composite layer on said wafer by a chemical vapor deposition process; said step of forming said composite layer further comprises depositing on said semiconductor wafer a mixture comprising: a) polycrystalline silicon, comprising the material which is convertible to an insulation material; and b) germanium, comprising the material which is convertible to a gas; and said step of converting said composite layer comprises simultaneously oxidizing said polycrystalline silicon to form silicon dioxide and oxidizing said carbon to produce gaseous germanium nitride.
Claim 11
Dependent Claim 41 words
The process of claim 8 wherein one or more materials which either are themselves insulation materials or are convertible to insulation materials comprise about 10 wt % to about 90 wt % of said composite layer prior to said converting step.
Claim 12
Dependent Claim 26 words
The process of claim 8 wherein said step of forming said composite layer further comprises forming said composite layer with one or more optional dopants present.
Claim 13
Dependent Claim 23 words
The process of claim 8 including the further step of heating said composite layer to planarize said layer prior to said converting step.
Claim 14
Dependent Claim 86 words
The process of claim 8 including the further steps of: a) forming one or more lower non-porous insulation layers on said integrated circuit structure prior to said step of forming said composite layer, to thereby present downward migration of impurities from said porous structure into said integrated circuit structure; and b) forming one or more upper non-porous insulation layers over said low dielectric constant insulation layer after said converting step to thereby prevent upward migration of impurities from said porous structure into said integrated circuit structure.
Claim 15
Dependent Claim 38 words
The process of claim 8 wherein said step of forming said composite layer on said semiconductor wafer by a chemical deposition process further comprises depositing said composite layer while maintaining a plasma during said chemical vapor deposition process.
Claim 16
Dependent Claim 69 words
The process of claim 12 including the further steps of: a) forming one or more contact openings in said one or more lower non-porous insulation layers, said low dielectric constant insulation layer, and said one or more upper non-porous insulation layers; b) filling said contact openings with conductive material; and c) forming a patterned metal layer over an upper surface of said one or more upper non-porous insulation layers.

References Cited (Backward Citations)

US4028149A Cited
US4532700A Cited
US5175130A Cited
US4968384A Cited
US5393712A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1999-02-26 1999-08-28 2000-02-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2003-02-26 2003-08-28 2004-02-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2007-02-26 2007-08-28 2008-02-27 $7700.00 Window Closed / Lapsed

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