US6737202B2
Expired / Lapsed
US
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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 07:43
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.
References Cited (Backward Citations)
EP0372790A2
Cited
US5122387A
Cited
US4975382A
Cited
US5338703A
Cited
JPH07201889A
Cited
JPH11150129A
Cited
US6051454A
Cited
US5981319A
Cited
US6387783B1
Cited
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 |