Patent US6737202B2 successfully refreshed from Google Patents.
US6737202B2
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Method of fabricating a tiered structure using a multi-layered resist stack and use
Assignee: NXP USA Inc
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Filing: 2002-02-22
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Granted: 2004-05-18
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Expires: 2022-02-22
Abstract
Abstract An improved and novel method of forming a tiered structure, such as a T-gate structure, including the fabrication of a stabilized resist layer that provides for the prevention of interlayer intermixing with the deposition of subsequent resist layers. The method includes patterning a base resist layer to provide for an opening which will form the stem of the tiered structure and subsequently stabilizing the resist base layer without deforming the stem opening. Next, a resist stack is deposited on an uppermost surface of the stabilized resist layer. Patterning the resist stack provides for an opening on an uppermost layer or portion, and a reentrant profile in a portion of the resist stack adjacent the stabilized resist layer. Metallization and subsequent removal of the resist layers results in a tiered structure, such as a T-gate structure, formed using only low to medium molecular weight, linear polymeric materials such as those used in positive optical resists in optical lithography.
Inventors
- 👤 Kathleen Ann Gehoski
- 👤 Laura Popovich
- 👤 David P. Mancini
- 👤 Doug J. Resnick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 23:09
CPC Classifications
H; H10; H10P; H10P76/00; H10P76/20; H10P76/202; H10D; H10D64/00; H10D64/20; H10D64/27; H10D64/311; H10D64/411; H10P76/204; H10P76/2041; Y; Y10; Y10S; Y10S438/00; Y10S438/942; Y10S438/948; Y10S438/951
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
150 words
A method of forming a tiered structure using a multi-layered resist stack comprising the steps of: providing a substrate having a surface; depositing and patterning a base resist layer on the surface of the substrate; stabilizing the patterned base resist layer, thereby forming a stabilized resist layer; forming a resist stack including an isotropically developing material formed on an uppermost surface of the stabilized resist layer and an imageable material formed on a surface of the isotropically developing material; patterning, in alignment with an opening defined in the stabilized resist layer, an opening in the resist stack having a reentrant profile and a dimension greater than the opening defined in the stabilized resist layer; depositing a metal material within the opening defined therein the resist stack and the opening defined therein the stabilized resist layer; and removing the resist stack and the stabilized resist layer, thereby exposing a tiered structure.
Claim 2
Independent Claim
150 words
A method of forming a tiered structure using a multi-layered resist stack comprising the steps of: providing a substrate having a surface; depositing and patterning a base resist layer on the surface of the substrate; stabilizing the patterned base resist layer, thereby forming a stabilized resist layer; forming a resist stack including an isotropically developing material formed on an uppermost surface of the stabilized resist layer and an imageable material formed on a surface of the isotropically developing material; patterning, in alignment with an opening defined in the stabilized resist layer, an opening in the resist stack having a reentrant profile and a dimension greater than the opening defined in the stabilized resist layer; depositing a metal material within the opening defined therein the resist stack and the opening defined therein the stabilized resist layer; and removing the resist stack and the stabilized resist layer, thereby exposing a tiered structure.
Claim 3
Dependent Claim
25 words
A method of forming a tiered structure using a multi-layered resist stack as claimed in claim 1 wherein the tiered structure is a T-gate structure.
Claim 4
Dependent Claim
36 words
A method of forming a tiered structure using a multi-layered resist stack as claimed in claim 2 wherein the step of providing a substrate having a surface includes providing a substrate formed of a semiconductor material.
Claim 5
Dependent Claim
38 words
A method of forming a tiered structure using a multi-layered resist stack as claimed in claim 1 wherein the step of depositing a base resist layer includes depositing a low to medium molecular weight, soluble, organic imageable material.
Claim 6
Dependent Claim
85 words
A method of forming a tiered structure using a multi-layered resist stack as claimed in claim 3 wherein the step of stabilizing the patterned base resist layer includes the step of exposing the base resist layer to one of a heat source, a light source, a heat source and a light source, an electron beam irradiation source, and an electron beam irradiation source and a heat source, thereby increasing the molecular weight of the base resist layer through cross-linking, forming the stabilized base resist layer.
Claim 7
Dependent Claim
38 words
A method of forming a tiered structure using a multi-layered resist stack as claimed in claim 5 wherein the step of exposing the base resist layer to a light source includes exposing to an deep ultraviolet light source.
Claim 8
Dependent Claim
41 words
A method of forming a tiered structure using a multi-layered resist stack as claimed in claim 5 wherein the step of depositing the resist stack on an uppermost surface of the stabilized resist layer includes forming a multiple layer resist stack.
Claim 9
Dependent Claim
31 words
A method of forming a tiered structure using a multi-layered resist stack as claimed in claim 5 wherein the step of depositing a metal material includes depositing a conductive metal material.
Claim 10
Dependent Claim
54 words
A method of forming a tiered structure using a multi-layered resist stack as claimed in claim 5 wherein the step of removing the resist slack and its stabilized base resist layer includes immersing the stack in a solvent bath immersion to remove the resist stack and etching to remove the stabilized base resist layer.
Claim 11
Independent Claim
237 words
A method of forming a tiered structure using a multi-layered resist stack comprising the steps of: providing a semiconductor substrate having a surface; depositing a soluble organic imageable material on the surface of the substrate, thereby forming a base resist layer; patterning the base resist layer to define therein an opening having a first dimension; stabilizing the base resist layer by exposing the base resist layer to one of a light source, a heat source, a combination of a light source and a heat source, an electron beam irradiation source, and a combination of an electron beam irradiation source and a heat source, thereby increasing the molecular weight of the base resist layer through cross-linking and forming a stabilized resist layer having an opening defined therein; forming a resist stack including an isotropically developing material formed on an uppermost surface of the stabilized resist layer and an imageable material formed on a surface of the isotropically developing material; patterning, in alignment with an opening defined in the stabilized resist layer, an opening in the imageable material and an opening in the isotropically developing material having a reentrant profile and a dimension greater than the opening defined in the stabilized resist layer; depositing a metal material within the openings defined therein the resist stack and the opening defined therein the stabilized resist layer; and removing the resist stack and the stabilized resist layer, thereby exposing a tiered structure.
Claim 12
Independent Claim
237 words
A method of forming a tiered structure using a multi-layered resist stack comprising the steps of: providing a semiconductor substrate having a surface; depositing a soluble organic imageable material on the surface of the substrate, thereby forming a base resist layer; patterning the base resist layer to define therein an opening having a first dimension; stabilizing the base resist layer by exposing the base resist layer to one of a light source, a heat source, a combination of a light source and a heat source, an electron beam irradiation source, and a combination of an electron beam irradiation source and a heat source, thereby increasing the molecular weight of the base resist layer through cross-linking and forming a stabilized resist layer having an opening defined therein; forming a resist stack including an isotropically developing material formed on an uppermost surface of the stabilized resist layer and an imageable material formed on a surface of the isotropically developing material; patterning, in alignment with an opening defined in the stabilized resist layer, an opening in the imageable material and an opening in the isotropically developing material having a reentrant profile and a dimension greater than the opening defined in the stabilized resist layer; depositing a metal material within the openings defined therein the resist stack and the opening defined therein the stabilized resist layer; and removing the resist stack and the stabilized resist layer, thereby exposing a tiered structure.
Claim 13
Dependent Claim
25 words
A method of forming a tiered structure using a multi-layered resist stack as claimed in claim 10 wherein the tiered structure is a T-gate structure.
Claim 14
Dependent Claim
49 words
A method of forming a tiered structure using a multi-layered resist stack as claimed in claim 10 wherein the step of providing a substrate having a surface includes providing a substrate formed of a semiconducting material chosen from the group consisting of: column III-V compound semiconductors, glass, metals, silicon.
Claim 15
Dependent Claim
38 words
A method of forming a tiered structure using a multi-layered resist stack as claimed in claim 10 wherein the step of depositing a base resist layer includes depositing a low to medium molecular weight soluble organic imageable material.
Claim 16
Dependent Claim
38 words
A method of forming a tiered structure using a multi-layered resist stack as claimed in claim 10 wherein the step of exposing the base resist layer to a light source includes exposing to a deep ultraviolet light source.
Claim 17
Dependent Claim
71 words
A method of forming a tiered structure using a multi-layered resist stack as claimed in claim 10 wherein the step of depositing a resist stack on an uppermost surface of the stabilized resist layer includes the step of creating a reentrant resist profile in the upper resist layer by diffusing a base into an uppermost portion of the resist stack, and defining an isotropically developed material adjacent the stabilized resist layer.
Claim 18
Dependent Claim
31 words
A method of forming a tiered structure using a multi-layered resist stack as claimed in claim 10 wherein the step of depositing a metal material includes depositing a conductive metal material.
Claim 19
Dependent Claim
52 words
A method of forming a tiered structure using a multi-layered resist stack as claimed in claim 10 wherein the step of removing the resist stack and the stabilized resist layer includes immersing the stack in a solvent bath immersion to remove the resist stack and etching to remove the stabilized resist layer.
Claim 20
Independent Claim
194 words
A method of forming a semiconductor device comprising the steps of: providing a substrate having a surface; forming a source on an uppermost surface of the substrate; forming a drain on an uppermost surface of the substrate; fabricating a tiered structure including the steps of: providing a substrate having a surface; depositing and patterning a base resist layer on the surface of the substrate; stabilizing the patterned base resist layer, thereby forming a stabilized resist layer; forming a resist stack including an isotropically developing material formed on an uppermost surface of the stabilized resist layer and an imageable material formed on a surface of the isotropically developing material; patterning, in alignment with an opening defined in the stabilized resist layer, an opening in the resist stack having a reentrant profile and a dimension greater than the opening defined in the stabilized resist layer; depositing a metal material within the opening defined therein the resist stack and the opening defined therein the stabilized resist layer; and removing the resist stack and the stabilized resist layer, thereby exposing a tiered structure; and positioning the tiered structure between the source and the drain, thereby forming a transistor.
Claim 21
Independent Claim
194 words
A method of forming a semiconductor device comprising the steps of: providing a substrate having a surface; forming a source on an uppermost surface of the substrate; forming a drain on an uppermost surface of the substrate; fabricating a tiered structure including the steps of: providing a substrate having a surface; depositing and patterning a base resist layer on the surface of the substrate; stabilizing the patterned base resist layer, thereby forming a stabilized resist layer; forming a resist stack including an isotropically developing material formed on an uppermost surface of the stabilized resist layer and an imageable material formed on a surface of the isotropically developing material; patterning, in alignment with an opening defined in the stabilized resist layer, an opening in the resist stack having a reentrant profile and a dimension greater than the opening defined in the stabilized resist layer; depositing a metal material within the opening defined therein the resist stack and the opening defined therein the stabilized resist layer; and removing the resist stack and the stabilized resist layer, thereby exposing a tiered structure; and positioning the tiered structure between the source and the drain, thereby forming a transistor.
Claim 22
Dependent Claim
39 words
A method of forming a semiconductor device as claimed in claim 18 wherein the step of depositing a base resist layer on the surface of the substrate includes depositing a low to medium molecular weight, soluble, organic imageable material.
Claim 23
Dependent Claim
91 words
A method of forming a tiered structure using a multi-layered resist stack as claimed in claim 19 wherein the step of stabilizing the patterned base resist layer includes the step of exposing the base resist layer to one of a heat source, a light source, a combination of a heat source and a light source, an electron beam irradiation source, and a combination of an electron beam irradiation source and a heat source, thereby increasing the molecular weight of the base resist layer through cross-linking and forming the stabilized resist layer.
Claim 24
Dependent Claim
38 words
A method of forming a tiered structure using a multi-layered resist stack as claimed in claim 20 wherein the step of exposing the base resist layer to a light source includes exposing to a deep ultraviolet light source.
Claim 25
Dependent Claim
58 words
A method of forming a tiered structure using a multi-layered resist stack as claimed in claim 20 wherein the step of removing the at least one resist layer and the stabilized resist layer includes immersing the stack in a solvent bath immersion to remove the at least one resist layer and etching to remove the stabilized resist layer.
Claim 26
Independent Claim
138 words
A method of forming a tiered structure using a multi-layered resist stack comprising the steps of: providing a substrate having a surface; depositing and patterning a base resist layer on the surface of the substrate; stabilizing the patterned base resist layer, thereby forming a stabilized resist layer; depositing a resist stack on an uppermost surface of the stabilized resist layer including the step of patterning a reentrant resist profile in the resist stack by diffusing a base into an uppermost portion at the resist stack, wherein the reentrant profile has a dimension greater than the opening defined in the stabilized resist layer, depositing a metal material within the opening defined therein the resist stack and the opening defined therein the stabilized resist layer; and removing the resist stack and the stabilized resist layer, thereby exposing a tiered structure.
Claim 27
Independent Claim
138 words
A method of forming a tiered structure using a multi-layered resist stack comprising the steps of: providing a substrate having a surface; depositing and patterning a base resist layer on the surface of the substrate; stabilizing the patterned base resist layer, thereby forming a stabilized resist layer; depositing a resist stack on an uppermost surface of the stabilized resist layer including the step of patterning a reentrant resist profile in the resist stack by diffusing a base into an uppermost portion at the resist stack, wherein the reentrant profile has a dimension greater than the opening defined in the stabilized resist layer, depositing a metal material within the opening defined therein the resist stack and the opening defined therein the stabilized resist layer; and removing the resist stack and the stabilized resist layer, thereby exposing a tiered structure.
Claim 28
Dependent Claim
48 words
A method of forming a tiered structure using a multi-layered resist stack as claimed in claim 23 wherein the step of depositing a resist stack on an uppermost surface of the stabilized resist layer includes the step of defining an isotropically developed material adjacent the stabilized resist 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) | 2007-05-18 | 2007-11-17 | 2008-05-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2011-05-18 | 2011-11-17 | 2012-05-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2015-05-18 | 2015-11-17 | 2016-05-18 | $7700.00 | Window Closed / Lapsed |