US6764949B2
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for reducing pattern deformation and photoresist poisoning in semiconductor device fabrication
Assignee: GlobalFoundries US Inc
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Filing: 2002-12-30
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Granted: 2004-07-20
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Expires: 2022-12-30
Abstract
Abstract A hardmask stack is comprised of alternating layers of doped amorphous carbon and undoped amorphous carbon. The undoped amorphous carbon layers serve as buffer layers that constrain the effects of compressive stress within the doped amorphous carbon layers to prevent delamination. The stack is provided with a top capping layer. The layer beneath the capping layer is preferably undoped amorphous carbon to reduce photoresist poisoning. An alternative hardmask stack is comprised of alternating layers of capping material and amorphous carbon. The amorphous carbon layers may be doped or undoped. The capping material layers serve as buffer layers that constrain the effects of compressive stress within the amorphous carbon layers to prevent delamination. The top layer of the stack is formed of a capping material. The layer beneath the top layer is preferably undoped amorphous carbon to reduce photoresist poisoning. The lowest layer of the hardmask stack is preferably amorphous carbon to facilitate easy removal of the hardmask stack from underlying materials by an ashing process.
Inventors
- 👤 Douglas J. Bonser
- 👤 Marina V. Plat
- 👤 Chih Yuh Yang
- 👤 Scott A. Bell
- 👤 Darin Chan
- 👤 Philip A. Fisher
- 👤 Christopher F. Lyons
- 👤 Mark S. Chang
- 👤 Pei-Yuan Gao
- 👤 Marilyn I. Wright
- 👤 Lu You
- 👤 Srikanteswara Dakshina-Murthy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 05:10
CPC Classifications
H; H10; H10P; H10P76/00; H10P76/40; H10P50/00; H10P50/71; H10P10/00; H10P76/405
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
121 words
A method for fabricating a semiconductor device comprising: providing a substrate comprising an upper layer of material; forming a hardmask stack on the upper layer of material, the hardmask stack comprising an amorphous carbon portion formed in contact with the layer of material, and a capping layer formed on the amorphous carbon portion, the amorphous carbon portion comprising alternating layers of doped amorphous carbon containing dopant for enhancing etch selectivity with respect to said upper layer of material, and undoped amorphous carbon containing essentially none of said dopant; forming a photoresist mask over the hardmask stack; and etching the hardmask stack using the photoresist mask as an initial etch mask to form a hardmask for patterning said upper layer of material.
Claim 2
Independent Claim
121 words
A method for fabricating a semiconductor device comprising: providing a substrate comprising an upper layer of material; forming a hardmask stack on the upper layer of material, the hardmask stack comprising an amorphous carbon portion formed in contact with the layer of material, and a capping layer formed on the amorphous carbon portion, the amorphous carbon portion comprising alternating layers of doped amorphous carbon containing dopant for enhancing etch selectivity with respect to said upper layer of material, and undoped amorphous carbon containing essentially none of said dopant; forming a photoresist mask over the hardmask stack; and etching the hardmask stack using the photoresist mask as an initial etch mask to form a hardmask for patterning said upper layer of material.
Claim 3
Dependent Claim
19 words
The method claimed in claim 1 , further comprising patterning said upper layer of material and removing the hardmask.
Claim 4
Dependent Claim
16 words
The method claimed in claim 2 , wherein the hardmask is removed by an ashing process.
Claim 5
Dependent Claim
64 words
The method claimed in claim 1 , wherein the amorphous carbon portion of the photoresist hardmask stack comprises: a lowermost layer of undoped amorphous carbon formed on said layer of material; an uppermost layer of undoped amorphous carbon formed in contact with said capping layer; and at least one layer of doped amorphous carbon between said uppermost and lowermost layers of undoped amorphous carbon.
Claim 6
Dependent Claim
55 words
The method claimed in claim 4 , wherein the amorphous carbon portion of the photoresist hardmask stack comprises: at least two layers of doped amorphous carbon between said uppermost and lowermost layers of undoped amorphous carbon; and at least one layer of undoped amorphous carbon between said at least two layers of doped amorphous carbon.
Claim 7
Dependent Claim
19 words
The method claimed in claim 1 , wherein said doped and undoped layers of amorphous carbon comprise discrete layers.
Claim 8
Dependent Claim
19 words
The method claimed in claim 1 , wherein said doped and undoped layers of amorphous carbon comprise continuous layers.
Claim 9
Dependent Claim
26 words
The method claimed in claim 1 , wherein forming said photoresist mask comprises: forming a photoresist pattern on said capping layer; and trimming said photoresist pattern.
Claim 10
Dependent Claim
16 words
The method claimed in claim 1 , wherein said doped amorphous carbon is doped with nitrogen.
Claim 11
Dependent Claim
36 words
The method claimed in claim 1 , wherein said substrate comprises a semiconductor substrate, and wherein said upper layer of material is a gate conductive material formed over a gate insulating material formed on said substrate.
Claim 12
Independent Claim
102 words
A method for fabricating a semiconductor device comprising: providing a substrate comprising an upper layer of material; forming a hardmask stack on the upper layer of material, the hardmask stack comprising alternating layers of capping material and amorphous carbon including at least an upper capping material layer and a lower capping material layer, and at least one amorphous carbon layer formed between the upper and lower capping material layers; forming a photoresist mask over the hardmask stack; and etching the hardmask stack using the photoresist mask as an initial etch mask to form a hardmask for patterning said upper layer of material.
Claim 13
Independent Claim
102 words
A method for fabricating a semiconductor device comprising: providing a substrate comprising an upper layer of material; forming a hardmask stack on the upper layer of material, the hardmask stack comprising alternating layers of capping material and amorphous carbon including at least an upper capping material layer and a lower capping material layer, and at least one amorphous carbon layer formed between the upper and lower capping material layers; forming a photoresist mask over the hardmask stack; and etching the hardmask stack using the photoresist mask as an initial etch mask to form a hardmask for patterning said upper layer of material.
Claim 14
Dependent Claim
19 words
The method claimed in claim 11 , further comprising patterning said upper layer of material and removing the hardmask.
Claim 15
Dependent Claim
38 words
The method claimed in claim 11 , wherein the hardmask stack further comprises a lower amorphous carbon layer formed on said upper layer of material, said lower capping material layer being formed on said lower amorphous carbon layer.
Claim 16
Dependent Claim
22 words
The method claimed in claim 13 , further comprising removing the hardmask from said upper layer of material by an ashing process.
Claim 17
Dependent Claim
27 words
The method claimed in claim 13 , wherein said lower amorphous carbon layer contains dopant for enhancing etch selectivity with respect to said upper layer of material.
Claim 18
Dependent Claim
12 words
The method claimed in claim 15 , wherein said dopant is nitrogen.
Claim 19
Dependent Claim
26 words
The method claimed in claim 11 , wherein forming said photoresist mask comprises: forming a photoresist pattern on said hardmask stack; and trimming said photoresist pattern.
Claim 20
Dependent Claim
36 words
The method claimed in claim 11 , wherein said substrate comprises a semiconductor substrate, and wherein said upper layer of material is a gate conductive material formed on a gate insulating material formed on said substrate.
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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) | 2007-07-20 | 2008-01-19 | 2008-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2011-07-20 | 2012-01-19 | 2012-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2015-07-20 | 2016-01-19 | 2016-07-20 | $7700.00 | Window Closed / Lapsed |