Patent US6365481B1 successfully refreshed from Google Patents.
US6365481B1
Expired / Lapsed
US
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Isotropic resistor protect etch to aid in residue removal
Assignee: GlobalFoundries US Inc
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Filing: 2000-09-13
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Granted: 2002-04-02
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Expires: 2020-09-13
Abstract
Abstract Various methods of fabricating a circuit structure, such as a gate electrode or a resistor are provided. In one aspect, a method of fabricating a circuit structure is provided that includes forming a silicon structure on a substrate and forming an oxide film on the silicon structure. A first portion of the oxide film is masked while a second portion is left unmasked. The second portion of the oxide film is removed by isotropic plasma etching to expose a portion of the silicon structure, and the first portion of the oxide film is unmasked. Use of isotropic etching for removal of a resistor protect oxide reduces the potential for isolation structure damage due to aggressive overetching associated with conventional anisotropic etching techniques.
Inventors
- 👤 Douglas J. Bonser
- 👤 Matthew Purdy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 06:09
CPC Classifications
H; H10; H10P; H10P10/00; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/283; H10D; H10D1/00; H10D1/40; H10D1/47
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
66 words
A method of fabricating a circuit structure, comprising: forming a silicon structure on a substrate; forming an oxide film on the silicon structure; masking a first portion of the oxide film while leaving a second portion unmasked; removing the second portion of the oxide film to expose a portion of the silicon structure by isotropic plasma etching; and unmasking the first portion of the oxide film.
Claim 2
Independent Claim
66 words
A method of fabricating a circuit structure, comprising: forming a silicon structure on a substrate; forming an oxide film on the silicon structure; masking a first portion of the oxide film while leaving a second portion unmasked; removing the second portion of the oxide film to expose a portion of the silicon structure by isotropic plasma etching; and unmasking the first portion of the oxide film.
Claim 3
Dependent Claim
18 words
The method of claim 1 , comprising forming a silicide film on the portion of the silicon structure.
Claim 4
Dependent Claim
25 words
The method of claim 2 , wherein forming of the silicide film comprises depositing cobalt and annealing the substrate to react the cobalt with silicon.
Claim 5
Dependent Claim
29 words
The method of claim 2 , wherein forming of the silicide film comprises depositing cobalt or titanium and annealing the substrate to react the cobalt or titanium with silicon.
Claim 6
Dependent Claim
26 words
The method of claim 1 , wherein the forming of the silicon structure comprises depositing polysilicon and patterning the polysilicon into a desired shape by etching.
Claim 7
Dependent Claim
20 words
The method of claim 1 , wherein the forming of the oxide film comprises depositing oxide by chemical vapor deposition.
Claim 8
Dependent Claim
17 words
The method of claim 1 , wherein the isotropic plasma etching comprises etching with CHF 3 .
Claim 9
Independent Claim
113 words
A method of fabricating a resistor structure on a substrate, comprising: forming a polysilicon structure on the substrate; forming an oxide film on the polysilicon structure; masking a first portion of the oxide film while leaving a second portion unmasked; removing the unmasked portion of the oxide film by isotropic plasma etching to expose a first portion of the polysilicon structure, a second portion of the polysilicon structure remaining covered by the first portion of the oxide and defining a resistor structure; and forming a silicide film on the first portion of the polysilicon structure, the first portion of the oxide film preventing silicide formation on the second portion of the polysilicon structure.
Claim 10
Independent Claim
113 words
A method of fabricating a resistor structure on a substrate, comprising: forming a polysilicon structure on the substrate; forming an oxide film on the polysilicon structure; masking a first portion of the oxide film while leaving a second portion unmasked; removing the unmasked portion of the oxide film by isotropic plasma etching to expose a first portion of the polysilicon structure, a second portion of the polysilicon structure remaining covered by the first portion of the oxide and defining a resistor structure; and forming a silicide film on the first portion of the polysilicon structure, the first portion of the oxide film preventing silicide formation on the second portion of the polysilicon structure.
Claim 11
Dependent Claim
25 words
The method of claim 8 , wherein forming of the silicide film comprises depositing cobalt and annealing the substrate to react the cobalt with silicon.
Claim 12
Dependent Claim
29 words
The method of claim 8 , wherein forming of the silicide film comprises depositing cobalt or titanium and annealing the substrate to react the cobalt or titanium with silicon.
Claim 13
Dependent Claim
26 words
The method of claim 8 , wherein the forming of the silicon structure comprises depositing polysilicon and patterning the polysilicon into a desired shape by etching.
Claim 14
Dependent Claim
20 words
The method of claim 8 , wherein the forming of the oxide film comprises depositing oxide by chemical vapor deposition.
Claim 15
Dependent Claim
17 words
The method of claim 8 , wherein the isotropic plasma etching comprises etching with CHF 3 .
Claim 16
Independent Claim
67 words
A method of fabricating a circuit structure, comprising: forming a polysilicon structure on a silicon substrate; forming an oxide film on the polysilicon structure; masking a first portion of the oxide film while leaving a second portion unmasked; removing the second portion of the oxide film to expose a portion of the polysilicon structure by isotopic plasma etching; and unmasking the first portion of the oxide film.
Claim 17
Independent Claim
67 words
A method of fabricating a circuit structure, comprising: forming a polysilicon structure on a silicon substrate; forming an oxide film on the polysilicon structure; masking a first portion of the oxide film while leaving a second portion unmasked; removing the second portion of the oxide film to expose a portion of the polysilicon structure by isotopic plasma etching; and unmasking the first portion of the oxide film.
Claim 18
Dependent Claim
18 words
The method of claim 14 , comprising forming a silicide film on the portion of the polysilicon structure.
Claim 19
Dependent Claim
25 words
The method of claim 15 , wherein forming of the silicide film comprises depositing cobalt and annealing the substrate to react the cobalt with silicon.
Claim 20
Dependent Claim
29 words
The method of claim 15 , wherein forming of the silicide film comprises depositing cobalt or titanium and annealing the substrate to react the cobalt or titanium with silicon.
Claim 21
Dependent Claim
26 words
The method of claim 14 , wherein the forming of the silicon structure comprises depositing polysilicon and patterning the polysilicon into a desired shape by etching.
Claim 22
Dependent Claim
20 words
The method of claim 14 , wherein the forming of the oxide film comprises depositing oxide by chemical vapor deposition.
Claim 23
Dependent Claim
17 words
The method of claim 14 , wherein the isotropic plasma etching comprises etching with CHF 3 .
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 2005-04-01 | 2005-10-01 | 2006-04-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2009-04-01 | 2009-10-01 | 2010-04-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2013-04-01 | 2013-10-01 | 2014-04-02 | $7700.00 | Window Closed / Lapsed |