US4803181A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for forming sub-micrometer patterns using silylation of resist side walls
Assignee: International Business Machines Corp
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Filing: 1987-03-17
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Granted: 1989-02-07
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Expires: 2007-03-17
Abstract
Abstract A process for forming sidewalls for use in the fabrication of semiconductor structures, where the thin, vertical sidewalls are "image transferred" to define sub-micron lateral dimensions. First, a patterned resist profile with substantially vertical edges is formed on a substrate on which the sidewalls are to be created. Then, the profile is soaked in a reactive organometallic silylation agent to silylate the top and the vertical edges of the resist to a predetermined depth, thereby rendering the profile surfaces highly oxygen etch resistant. In a subsequent anisotropic RIE process, the horizontal surfaces of the silylated profile and the unsilylated resist are removed, leaving the silylated vertical edges, that provide the desired free-standing sidewalls, essentially unaffected.
Inventors
- 👤 Peter L. Buchmann
- 👤 Peter Vettiger
- 👤 Bart J. Van Zeghbroech
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:53
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/26; G03F7/40; G03F7/405; Y; Y10; Y10S; Y10S148/00; Y10S148/051; Y10S148/111; Y10S148/137; Y10S438/00; Y10S438/942; Y10S438/947; Y10S438/948; Y10S438/949; Y10S438/95
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
125 words
A low temperature process for forming sidewalls on a substrate for use in the fabrication of structures with sub-micron lateral dimensions comprising the steps of: depositing on said substrate a layer of polymeric resist comprising active hydrogen; patterning said resist thereby forming a profile having horizontal surfaces and substantially vertical edges; treating the maskless resist with a reactive organometallic silylation solution comprising Xylene, HMCTS and n-Methylpyrrolidone, respectively amounting to 89, 10 and 1 volume %, at a temperature of between 15° and 25° C., thereby silylating the exposed horizontal and vertical edges in said resist to a predetermined depth; and anisotropic oxygen plasma etching said resist thereby removing the silylated resist at said horizontal surfaces and removing the unsilylated resist, leaving the silylated vertical edges.
Claim 2
Dependent Claim
125 words
A low temperature process for forming sidewalls on a substrate for use in the fabrication of structures with sub-micron lateral dimensions comprising the steps of: depositing on said substrate a layer of polymeric resist comprising active hydrogen; patterning said resist thereby forming a profile having horizontal surfaces and substantially vertical edges; treating the maskless resist with a reactive organometallic silylation solution comprising Xylene, HMCTS and n-Methylpyrrolidone, respectively amounting to 89, 10 and 1 volume %, at a temperature of between 15° and 25° C., thereby silylating the exposed horizontal and vertical edges in said resist to a predetermined depth; and anisotropic oxygen plasma etching said resist thereby removing the silylated resist at said horizontal surfaces and removing the unsilylated resist, leaving the silylated vertical edges.
Claim 3
Dependent Claim
175 words
Low temperature process for fabricating a line pattern of sub-micron dimensions on a semiconductor body, characterized in that it comprises the steps of: depositing a film of the material from which the line pattern is to be formed on the semiconductor body; depositing, on said film, a layer of polymeric resist comprising active hydrogen; patterning said resist thereby forming a profile having horizontal surfaces and substantially vertical edges; silylating the maskless resist by treating said resist with a reactive organometallic silylation solution comprising Xylene, HMCTS and n-Methylpyrrolidone, respectively amounting to 89, 10 and 1 volume %, at a temperature of between 15° and 25° C., thereby replacing the active hydrogens with silicon atoms in the horizontal surfaces and the substantially vertical edges of the resist to a predetermined depth; dry etching said resist thereby removing the silylated resist at said horizontal surfaces and, removing the unsilylated resist, leaving the silylated, substantially vertical edges, on said film; anisotropically etching said film not covered by said substantially vertical edges of silylated resist; and removing said silylated resist.
Claim 4
Dependent Claim
175 words
Low temperature process for fabricating a line pattern of sub-micron dimensions on a semiconductor body, characterized in that it comprises the steps of: depositing a film of the material from which the line pattern is to be formed on the semiconductor body; depositing, on said film, a layer of polymeric resist comprising active hydrogen; patterning said resist thereby forming a profile having horizontal surfaces and substantially vertical edges; silylating the maskless resist by treating said resist with a reactive organometallic silylation solution comprising Xylene, HMCTS and n-Methylpyrrolidone, respectively amounting to 89, 10 and 1 volume %, at a temperature of between 15° and 25° C., thereby replacing the active hydrogens with silicon atoms in the horizontal surfaces and the substantially vertical edges of the resist to a predetermined depth; dry etching said resist thereby removing the silylated resist at said horizontal surfaces and, removing the unsilylated resist, leaving the silylated, substantially vertical edges, on said film; anisotropically etching said film not covered by said substantially vertical edges of silylated resist; and removing said silylated resist.
Claim 5
Dependent Claim
23 words
A process as claimed in claim 2, wherein the film from which the line pattern is to be formed consists of a metal.
Claim 6
Dependent Claim
17 words
A process as claimed in claim 3, wherein the film consists of tungsten silicide (WSi x ).
Claim 7
Dependent Claim
42 words
A process as claimed in claim 2 further comprising a step following said etching step, comprising removing selected portions of said vertical silylated resist leaving only those sidewalls corresponding to the line pattern which is to be formed in the underlying layer.
Claim 8
Dependent Claim
20 words
The process of claim 4 wherein said removing comprises selectively reactive ion etching using O 2 /10% CF 4 RIE.
Claim 9
Dependent Claim
14 words
The process of claim 2 wherein said etching of said resist comprises anisotropic etching.
Claim 10
Dependent Claim
19 words
The process of claim 2 wherein said etching of said resist comprises anisotropic etching reactive ion etching comprising oxygen.
Claim 11
Dependent Claim
40 words
The process of claim 2 wherein said etching of said resist comprises; a first step comprising anisotropically etching said silylated resist by halogen enhanced exygen RIE; and a second step comprising said unsilylated resist by an O 2 plasma etch.
Claim 12
Dependent Claim
19 words
The process of claim 2 wherein said first etching step is by an O 2 /10% CF 4 RIE.
Claim 13
Dependent Claim
133 words
A low temperature process for forming sidewalls on a substrate for use in the fabrication of structures having sub-micron lateral dimensions comprising the steps of: depositing on said substrate a layer of polymeric material comprising active hydrogen; patterning said polymeric material, said pattern having horizontal surfaces and substantially vertical surfaces; forming a sub-micron structure in said horizontal and substantially vertical surfaces of said polymeric material by silylating said material by treating said material with a solution comprising Xylene, HMCTS and n-methylpyrrolidone, respectively amounting to 89, 10 and 1 volume %, at a temperature of between 15° and 25° C., to a predetermined depth; and etching said polymeric material thereby removing said sub-micron structure in said horizontal surfaces and said polymeric material and whereby said submicron structure formed in said substantially vertical surfaces remains.
Claim 14
Dependent Claim
133 words
A low temperature process for forming sidewalls on a substrate for use in the fabrication of structures having sub-micron lateral dimensions comprising the steps of: depositing on said substrate a layer of polymeric material comprising active hydrogen; patterning said polymeric material, said pattern having horizontal surfaces and substantially vertical surfaces; forming a sub-micron structure in said horizontal and substantially vertical surfaces of said polymeric material by silylating said material by treating said material with a solution comprising Xylene, HMCTS and n-methylpyrrolidone, respectively amounting to 89, 10 and 1 volume %, at a temperature of between 15° and 25° C., to a predetermined depth; and etching said polymeric material thereby removing said sub-micron structure in said horizontal surfaces and said polymeric material and whereby said submicron structure formed in said substantially vertical surfaces remains.
Claim 15
Dependent Claim
15 words
The process of claim 11 wherein said etching of said polymeric material comprises anisotropic etching.
Claim 16
Dependent Claim
18 words
The process of claim 11 wherein said etching of said polymeric material comprises anisotropic ion etching comprising oxygen.
Claim 17
Dependent Claim
39 words
The process of claim 11 wherein said etching comprises; a first etching step comprising anisotropically etching said silylated resist by halogen enhanced oxygen RIE; and a second etching step comprising etching said unsilylated resist by an oxygen plasma etch.
Claim 18
Dependent Claim
18 words
The process of claim 14 wherein said first etching step is by O 2 /10% CF 4 RIE.
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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) | 1992-02-07 | 1992-08-08 | 1993-02-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-02-07 | 1996-08-08 | 1997-02-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-02-07 | 2000-08-08 | 2001-02-07 | $7700.00 | Window Closed / Lapsed |