US4673592A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Metal planarization process
Assignee: Texas Instruments Inc
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Filing: 1982-06-02
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Granted: 1987-06-16
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Expires: 2002-06-02
Abstract
Abstract The present invention discloses a method for planarizing contact holes, vias, and other surface depressions, during the fabrication of an integrated circuit structure. Differential thermal conductivities are exploited to selectively remove a deposited film of metal from high-thermal-resistance areas, such as silicon dioxide or other insulators, and not from low-thermal-resistance areas, such as silicon or metal. By repetition of this step, very deep depressions, having a high aspect ratio, are reliably filled.
Inventors
- 👤 Vernon R. Porter
- 👤 Samuel C. Baber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:30
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/056; H10W20/062
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
130 words
A process for filling recesses in a low-thermal-conductivity material, comprising the steps of: providing a high-thermal-conductivity first layer; depositing a low-thermal-conductivity additional layer above said first layer; etching a contact hole through a selected portion of said low-thermal-conductivity layer to expose said first layer; depositing a high-thermal-conductivity top layer overall; irradiating said top layer at a power density greater that 1 kW per square centimeter and an energy density of greater than 0.05 Joules per square centimeter, whereby said top layer loses its adhesion to said low-thermal-conductivity layer; mechanically removing remaining portions of said top layer from above said low-thermal-conductivity layer; and repeating said deposition, irradiation, and removal steps until said selected portion of said additional layer has been filled to at least the approximate height of said additional layer.
Claim 2
Dependent Claim
130 words
A process for filling recesses in a low-thermal-conductivity material, comprising the steps of: providing a high-thermal-conductivity first layer; depositing a low-thermal-conductivity additional layer above said first layer; etching a contact hole through a selected portion of said low-thermal-conductivity layer to expose said first layer; depositing a high-thermal-conductivity top layer overall; irradiating said top layer at a power density greater that 1 kW per square centimeter and an energy density of greater than 0.05 Joules per square centimeter, whereby said top layer loses its adhesion to said low-thermal-conductivity layer; mechanically removing remaining portions of said top layer from above said low-thermal-conductivity layer; and repeating said deposition, irradiation, and removal steps until said selected portion of said additional layer has been filled to at least the approximate height of said additional layer.
Claim 3
Dependent Claim
116 words
A process for filling recesses in a low-thermal-conductivity material, comprising the steps of: providing a high-thermal-conductivity substrate; depositing one or more low-thermal-conductivity layers above said substrate; etching a contact hole through a selected portion of said low-thermal-conductivity layer to expose said substrate; depositing a composite top layer film over all; irradiating said top layer, at a total energy density which is greater than 10 microJoules per square centimeter per nanometer of thickness of said top layer, whereby said top layer loses adhesion to said low-thermal-conductivity layer; mechanically removing portions of said top layer from above said low-thermal-conductivity layer; and repeating said deposition, irradiation, and removal steps until said contact hole has been filled with said metal.
Claim 4
Dependent Claim
116 words
A process for filling recesses in a low-thermal-conductivity material, comprising the steps of: providing a high-thermal-conductivity substrate; depositing one or more low-thermal-conductivity layers above said substrate; etching a contact hole through a selected portion of said low-thermal-conductivity layer to expose said substrate; depositing a composite top layer film over all; irradiating said top layer, at a total energy density which is greater than 10 microJoules per square centimeter per nanometer of thickness of said top layer, whereby said top layer loses adhesion to said low-thermal-conductivity layer; mechanically removing portions of said top layer from above said low-thermal-conductivity layer; and repeating said deposition, irradiation, and removal steps until said contact hole has been filled with said metal.
Claim 5
Dependent Claim
31 words
The process of claim 1 or 2, wherein said top layer comprises a composite material having first and second components, one of said components of said composite material being a metal.
Claim 6
Dependent Claim
37 words
The process of claim 3, wherein said first and second components of said composite material have respective separate volumes which are in sum greater than the volume of an alloy formed from said first and second materials.
Claim 7
Dependent Claim
15 words
The process of claim 1 or 2, wherein said top layer comprises a metal silicide.
Claim 8
Dependent Claim
15 words
The method of claim 1 or 2, wherein said top layer comprises an intermetallic compound.
Claim 9
Dependent Claim
18 words
The process of claim 1 or 2, wherein said top layer comprises a mixture of titanium and tungsten.
Claim 10
Dependent Claim
15 words
The process of claim 1 or 2, wherein said top layer is deposited by sputtering.
Claim 11
Dependent Claim
15 words
The method of claim 1 or 2, wherein said top layer is deposited in tension.
Claim 12
Dependent Claim
18 words
The process of claim 4, wherein said top layer is deposited by sputtering in an approximately amorphous condition.
Claim 13
Dependent Claim
13 words
The process of claim 10, wherein said top layer is deposited in tension.
Claim 14
Dependent Claim
109 words
A process for filling recesses in a low-thermal-conductivity material, comprising the steps of: providing a high-thermal-conductivity first layer; depositing a low-thermal-conductivity second layer above said first layer; etching a contact hole through a selected portion of said second layer, to expose said first layer; depositing a high-thermal-conductivity top layer overall; irradiating said top layer at an energy density which is greater than 0.1 Joules per square centimeter, whereby portions of said top layer which are not in contact with said high-thermal-conductivity first layer are vaporized; and repeating said deposition, and irradiation steps until said contact hole has been filled to at least the approximate height of said second layer.
Claim 15
Dependent Claim
109 words
A process for filling recesses in a low-thermal-conductivity material, comprising the steps of: providing a high-thermal-conductivity first layer; depositing a low-thermal-conductivity second layer above said first layer; etching a contact hole through a selected portion of said second layer, to expose said first layer; depositing a high-thermal-conductivity top layer overall; irradiating said top layer at an energy density which is greater than 0.1 Joules per square centimeter, whereby portions of said top layer which are not in contact with said high-thermal-conductivity first layer are vaporized; and repeating said deposition, and irradiation steps until said contact hole has been filled to at least the approximate height of said second layer.
Claim 16
Dependent Claim
11 words
The method of claim 12, wherein said second layer comprises oxide.
Claim 17
Dependent Claim
30 words
The method of claim 12, wherein said irradiation step is applied at an energy density which is at least one milliJoule for each nanometer of thickness of said top layer.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-06-15 | 1990-12-15 | 1991-06-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-06-15 | 1994-12-15 | 1995-06-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-06-15 | 1998-12-15 | 1999-06-16 | $7700.00 | Window Closed / Lapsed |