US5071789A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for forming a metal electrical connector to a surface of a semiconductor device adjacent a sidewall of insulation material with metal creep-up extending up that sidewall, and related device
Assignee: Toshiba Corp
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Filing: 1990-06-12
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Granted: 1991-12-10
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Expires: 2010-06-12
Abstract
Abstract Contact with a substrate or conductor underlying an opening in the insulating layer is made by depositing a thin film of high melting point metal using a selective vapor phase growth process so that the metal film grows across the exposed surface and then creeps-up the sidewalls of the insulating layer. Electrical contact is completed by covering the thin film with a thicker growth of high melting point metal, preferably using a second selective vapor phase growth process, and then depositing a conducting film over the insulating layer in electrical contact with the thicker growth of metal.
Inventors
- 👤 Rempei Nakata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 23:17
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/056; H10W20/057; H10W20/40; H10W20/41; H10W20/425
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
200 words
A method of forming an electrical connection to a silicon surface of a semiconductor device adjacent a sidewall of insulating material comprising the steps of: a. exposing said surface to a halogenated gas of a metal with a high melting point under conditions to reduce said gas with said silicon to result in formation of a layer of said metal having a saturated thickness on said surface, said conditions being selected such that: (i) the saturated thickness of said layer is dependent upon the temperature od depostion, (ii) the saturated thickness of said layer increases with a higher temperature of deposition until an initial maximum thickness is obtainable at a first temperature of deposition and (iii) the saturated thickness of said layer decreases from said initial maximum thickness as the temperature increases from said first temperature of deposition until a second temperature is reached at which a minimized thickness is obtainable, said conditions including deposition of said layer at said second temperature to essentially minimize the saturated thickness of said layer, with said layer also being formed extending up said sidewall; and b. forming a conductor in electrical contact with said layer to thereby form electrical connection with said surface.
Claim 2
Independent Claim
200 words
A method of forming an electrical connection to a silicon surface of a semiconductor device adjacent a sidewall of insulating material comprising the steps of: a. exposing said surface to a halogenated gas of a metal with a high melting point under conditions to reduce said gas with said silicon to result in formation of a layer of said metal having a saturated thickness on said surface, said conditions being selected such that: (i) the saturated thickness of said layer is dependent upon the temperature od depostion, (ii) the saturated thickness of said layer increases with a higher temperature of deposition until an initial maximum thickness is obtainable at a first temperature of deposition and (iii) the saturated thickness of said layer decreases from said initial maximum thickness as the temperature increases from said first temperature of deposition until a second temperature is reached at which a minimized thickness is obtainable, said conditions including deposition of said layer at said second temperature to essentially minimize the saturated thickness of said layer, with said layer also being formed extending up said sidewall; and b. forming a conductor in electrical contact with said layer to thereby form electrical connection with said surface.
Claim 3
Dependent Claim
28 words
A method of claim 1 wherein said gas used in said step of exposing is WF 6 , MoF 6 , TaF 6 , or TiF 6 .
Claim 4
Dependent Claim
16 words
A method of claim 2 wherein said conditions include exposing said surface to a rare gas.
Claim 5
Dependent Claim
13 words
A method of claim 3 wherein said rare gas is Ar or He.
Claim 6
Dependent Claim
16 words
A method of claim 2 wherein said conditions include exposing said surface to N 2 gas.
Claim 7
Dependent Claim
18 words
A method of claim 1 wherein said high temperature is set ±30 degrees Celsius of said second temperature.
Claim 8
Dependent Claim
13 words
A method of claim 1 wherein said second temperature is 550 degrees Celsius.
Claim 9
Dependent Claim
26 words
A method of claim 7 wherein said conditions further include a reactor of 0.2 Torr and a partial pressure for said halogenated gas of 0.01 Torr.
Claim 10
Dependent Claim
13 words
A method of claim 8 wherein said halogenated gas is WF 6 .
Claim 11
Independent Claim
39 words
A method of claims 1, 2, 3, 4, 5, 6, 7, 8, or 9 wherein said step of exposing is continued until said metal extends up said sidewall a distance greater than three times the thickness of said layer.
Claim 12
Dependent Claim
30 words
A method of claim 10 wherein said step of exposing is continued until said metal extends up said sidewall a distance greater than ten times the thickness of said layer.
Claim 13
Independent Claim
22 words
A method of claims 1, 2, 3, 4, 5, 6, 7, 8, or 9 wherein said insulating layer is SiO 2 .
Claim 14
Dependent Claim
74 words
A method of claim 1 further comprising the steps of: c. exposing said layer of said metal to a mixture gas of said halogenated gas of a metal and a hydrogen gas to form an additional metal layer on said layer, wherein said step c is performed between said steps a and b, and said layer of said step a is obtained substantially only by the reducing of said halogenated gas with said silicon.
Claim 15
Dependent Claim
30 words
A method of claim 13 wherein said step c is performed until a contact hole which comprises said sidewall of said insulating material is buried with said additional metal layer.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-12-09 | 1995-06-10 | 1995-12-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-12-09 | 1999-06-10 | 1999-12-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-12-09 | 2003-06-10 | 2003-12-10 | $7700.00 | Window Closed / Lapsed |