Patent JPS5268938A successfully refreshed from Google Patents.
US5284804A
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US
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Global planarization process
Assignee: Texas Instruments Inc
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Filing: 1991-12-31
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Granted: 1994-02-08
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Expires: 2011-12-31
Abstract
Abstract A novel global planarization process is disclosed which is fully compatible with semiconductor processing. The process disclosed is called metal melt-solidification planarization (MMSP). A layer of a low melting point/high boiling point metal such as tin or a suitable alloy is deposited on a nonplanar wafer surface via physical-vapor deposition or chemical-vapor deposition or evaporation or plating. The wafer is then heated to above the tin melting point, cooled back to resolidify tin, and etched back to form a globally planar surface.
Inventors
- 👤 Mehrdad M. Moslehi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 05:10
CPC Classifications
H; H10; H10P; H10P76/00; H10P76/20; H10P76/204; H10P76/2041; H10P52/00; H10P52/40; H10P52/403; H10P95/00; H10P95/06
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
68 words
A method of planarizing a structure lying on a substrate comprising: depositing a disposable planarization layer which is in solid form at room temperature; forming a liquid melt from said planarization layer over the substrate so as to form a planar liquid melt surface; solidifying said melt so as to form a planar solid layer; etching back said planar solid layer to a predetermined level on said structure.
Claim 2
Independent Claim
68 words
A method of planarizing a structure lying on a substrate comprising: depositing a disposable planarization layer which is in solid form at room temperature; forming a liquid melt from said planarization layer over the substrate so as to form a planar liquid melt surface; solidifying said melt so as to form a planar solid layer; etching back said planar solid layer to a predetermined level on said structure.
Claim 3
Dependent Claim
25 words
A method as recited in claim 1 wherein said liquid melt is formed from a material having greater surface tension forces than forces of viscosity.
Claim 4
Dependent Claim
15 words
A method as recited in claim 1 wherein said substrate is formed of semiconductor material.
Claim 5
Independent Claim
71 words
A method of planarizing an interlevel dielectric layer on a substrate comprising: placing an interlevel dielectric layer over said substrate; placing an adhesion layer over said interlevel dielectric; placing a planarization layer over said adhesion layer; melting, planarizing and resolidifying said planarization layer via heating and cooling said substrate; and etching-back said planarization layer into said interlevel dielectric layer so as to form a planar surface on said interlevel dielectric layer.
Claim 6
Independent Claim
71 words
A method of planarizing an interlevel dielectric layer on a substrate comprising: placing an interlevel dielectric layer over said substrate; placing an adhesion layer over said interlevel dielectric; placing a planarization layer over said adhesion layer; melting, planarizing and resolidifying said planarization layer via heating and cooling said substrate; and etching-back said planarization layer into said interlevel dielectric layer so as to form a planar surface on said interlevel dielectric layer.
Claim 7
Dependent Claim
31 words
A method as recited in claim 4 wherein said etch-back is performed with an etch process including a 1-to-1 etchant selectivity as between said planarization layer and said interlevel dielectric layer.
Claim 8
Dependent Claim
27 words
A method as recited in claim 4 wherein a barrier layer is placed on said interlevel dielectric and said adhesion layer is placed over said barrier layer.
Claim 9
Dependent Claim
19 words
A method as recited in claim 6 wherein said barrier layer comprises Si 3 N 4 or silicon oxynitride.
Claim 10
Dependent Claim
18 words
A method as recited in claim 6 wherein said barrier layer is a plasma deposited silicon nitride material.
Claim 11
Dependent Claim
16 words
A method as recited in claim 4 wherein said interlevel dielectric is deposited over said substrate.
Claim 12
Dependent Claim
32 words
A method as recited in claim 4 wherein said interlevel dielectric layer comprises a dielectric selected from the group consisting of phosophosilicate glass or borophosphosilicate glass, undoped oxide or a combination thereof.
Claim 13
Dependent Claim
24 words
A method as recited in claim 4 wherein said adhesion layer comprises a material selected from the group consisting of titanium, silicon or aluminum.
Claim 14
Dependent Claim
23 words
A method as recited in claim 11 wherein said adhesion layer comprises a material selected from the group consisting of TiW or TiN.
Claim 15
Dependent Claim
31 words
A method as recited in claim 4 wherein said planarization layer is selected from the group consisting of tin, tin alloy, bismuth, bismuth alloy, indium, indium alloy, or a combination thereof.
Claim 16
Dependent Claim
20 words
A method as recited in claim 4 wherein said adhesion layer serves as a buffer against contaminants to said substrate.
Claim 17
Dependent Claim
28 words
A method as recited in claim 4 wherein said adhesion layer is deposited according to a method selected from the group consisting of physical-vapor deposition or chemical-vapor deposition.
Claim 18
Dependent Claim
31 words
A method as recited in claim 4 wherein said planarization layer is deposited over said adhesion layer according to a physical-deposition process or chemical-deposition process or an evaporation or plating process.
Claim 19
Independent Claim
64 words
A method of planarizing an interlevel dielectric layer on a substrate comprising: placing an interlevel dielectric layer over said substrate; placing an adhesion layer over said interlevel dielectric; placing a planarization layer over said adhesion layer; melting, planarizing, and resolidifying said planarization layer via heating and cooling said substrate; etching-back said planarization layer into said interlevel dielectric layer until detecting an etch-back end-point level.
Claim 20
Independent Claim
64 words
A method of planarizing an interlevel dielectric layer on a substrate comprising: placing an interlevel dielectric layer over said substrate; placing an adhesion layer over said interlevel dielectric; placing a planarization layer over said adhesion layer; melting, planarizing, and resolidifying said planarization layer via heating and cooling said substrate; etching-back said planarization layer into said interlevel dielectric layer until detecting an etch-back end-point level.
Claim 21
Dependent Claim
21 words
A method as recited in claim 17 wherein said etch-back end-point level is detected using a method of measuring surface reflectance.
Claim 22
Dependent Claim
21 words
A method as recited in claim 17 wherein said etch-back end-point is detected using a method of measuring electrical sheet resistance.
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| 3.5 Years (Year 4) | 1997-02-07 | 1997-08-09 | 1998-02-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-02-07 | 2001-08-09 | 2002-02-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-02-07 | 2005-08-09 | 2006-02-08 | $7700.00 | Window Closed / Lapsed |