US4902533A
Expired / Lapsed
US
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Method for selectively depositing tungsten on a substrate by using a spin-on metal oxide
Assignee: Motorola Solutions Inc
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Filing: 1987-06-19
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Granted: 1990-02-20
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Expires: 2007-06-19
Abstract
Abstract A process for selectively depositing a metal such as tungsten on a substrate material is provided. In one form, a layer of insulating material such as silicon dioxide is formed on the substrate. A layer of either aluminum oxide or titanium oxide is then formed over the substrate by a spin-on technique. A straight-wall contact region to the substrate is formed and tungsten may then be quickly and selectively formed in the contact region only with chemical vapor deposition at a high pressure. In another form, the aluminum oxide or titanium oxide layer may be thickly formed directly above the substrate without the silicon dioxide layer being formed.
Inventors
- 👤 Ted R. White
- 👤 Jeff L. Klein
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 20:46
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/056; H10W20/057; C; C23; C23C; C23C16/00; C23C16/04; H10P; H10P14/00; H10P14/40; H10P14/42; H10P14/43; H10P14/432
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
152 words
A method for selectively depositing tungsten on a semiconductor substrate during formation of an electronic device, comprising the sequential steps of: providing a substrate material; forming a layer either of aluminum oxide or titanium oxide above the substrate material; forming a contact/via area with the substrate material by removing the layer of either aluminum oxide or titanium oxide in a predetermined area above the substrate material and elsewhere maintaining either the aluminum oxide or titanium oxide exposed at a top surface of the device; placing the device in a chemical vapor deposition reactor and heating the substrate to a predetermined temperature; coupling tungsten hexafloride, a predetermined reducing gas, and a predetermined inert carrier gas into the reactor; and selectively depositing tungsten on the substrate material to a predetermined thickness by vapor deposition substantially without depositing the tungsten either on the aluminum oxide or titanium oxide at the top surface of the device.
Claim 2
Independent Claim
152 words
A method for selectively depositing tungsten on a semiconductor substrate during formation of an electronic device, comprising the sequential steps of: providing a substrate material; forming a layer either of aluminum oxide or titanium oxide above the substrate material; forming a contact/via area with the substrate material by removing the layer of either aluminum oxide or titanium oxide in a predetermined area above the substrate material and elsewhere maintaining either the aluminum oxide or titanium oxide exposed at a top surface of the device; placing the device in a chemical vapor deposition reactor and heating the substrate to a predetermined temperature; coupling tungsten hexafloride, a predetermined reducing gas, and a predetermined inert carrier gas into the reactor; and selectively depositing tungsten on the substrate material to a predetermined thickness by vapor deposition substantially without depositing the tungsten either on the aluminum oxide or titanium oxide at the top surface of the device.
Claim 3
Dependent Claim
36 words
The method of claim 1 further comprising the step of: forming a layer of insulating material directly on the substrate material before forming the layer of either aluminum oxide or titanium oxide above the silicon substrate.
Claim 4
Dependent Claim
30 words
The method of claim 1 wherein tungsten is selectively deposited by vapor deposition at a partial pressure of WF 6 substantially in the range of five to five hundred milliTorr.
Claim 5
Dependent Claim
23 words
The method of claim 2 wherein the insulating material is one of either borophosphosilicate glass, phosphosilicate glass or an undoped low temperature oxide.
Claim 6
Dependent Claim
26 words
The method of claim 1 wherein the contact/via area is formed by a selective photolithographic etching of the layer of either aluminum oxide or titanium oxide.
Claim 7
Dependent Claim
21 words
The method of claim 1 wherein the tungsten hexafloride has a partial pressure of substantially three hundred milliTorr in the reactor.
Claim 8
Dependent Claim
158 words
A process for selectively forming a metal on a substrate surface via chemical vapor deposition (CVD) during formation of an electronic device, comprising the sequential steps of: providing a substrate material; forming an insulating material on a top surface of the substrate material; forming a layer of aluminum oxide on a top surface of the insulating material; forming a contact/via area with the substrate material by removing the insulating material and aluminum oxide layer above a predetermined portion of the substrate material and maintaining the aluminum oxide exposed on a top surface of the device; placing the device in a chemical vapor deposition reactor and heating the substrate to a predetermined temperature; coupling tungsten hexafloride, a predetermined reducing gas, and a predetermined inert carrier gas into the reactor; and selectively depositing the metal on the substrate material to a predetermined thickness by vapor deposition substantially without depositing the metal on a top surface of the aluminum oxide layer.
Claim 9
Dependent Claim
158 words
A process for selectively forming a metal on a substrate surface via chemical vapor deposition (CVD) during formation of an electronic device, comprising the sequential steps of: providing a substrate material; forming an insulating material on a top surface of the substrate material; forming a layer of aluminum oxide on a top surface of the insulating material; forming a contact/via area with the substrate material by removing the insulating material and aluminum oxide layer above a predetermined portion of the substrate material and maintaining the aluminum oxide exposed on a top surface of the device; placing the device in a chemical vapor deposition reactor and heating the substrate to a predetermined temperature; coupling tungsten hexafloride, a predetermined reducing gas, and a predetermined inert carrier gas into the reactor; and selectively depositing the metal on the substrate material to a predetermined thickness by vapor deposition substantially without depositing the metal on a top surface of the aluminum oxide layer.
Claim 10
Dependent Claim
18 words
The process of claim 7 wherein the contact/via area which is formed is substantially a straight wall contact/via.
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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) | 1993-02-19 | 1993-08-21 | 1994-02-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-02-19 | 1997-08-21 | 1998-02-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-02-19 | 2001-08-21 | 2002-02-20 | $7700.00 | Window Closed / Lapsed |