Patent US5876903A successfully refreshed from Google Patents.
US5876903A
Expired / Lapsed
US
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Virtual hard mask for etching
Assignee: GlobalFoundries Inc
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Filing: 1996-12-31
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Granted: 1999-03-02
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Expires: 2016-12-31
Abstract
Abstract A method of hardening photoresist (24) by bombardment with ionized particles (42), such as argon. Ionic bombardment causes formation of a hardened skin (22) on the exposed top (30) and side walls (32) of the photoresist (24). The hardened skin erodes at a reduced rate during etching and is less likely to react with products created during etching, thereby allowing etching of more accurate line widths and gaps.
Inventors
- 👤 Che-Hoo Ng
- 👤 Bhanwar Singh
- 👤 Shekhar Pramanick
- 👤 Subash Gupta
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:49
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/26; G03F7/40; H; H10; H10P; H10P76/00; H10P76/20; H10P76/204; H10P76/2041; G03F7/20; G03F7/2022; G03F7/2024; G03F7/203
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
110 words
A method for processing a semiconductor wafer comprising the steps of: a) applying photoresist to a surface of the wafer; b) patterning the photoresist to create a patterned resist having side walls and top surfaces; c) hardening the patterned photoresist by bombarding the photoresist with ions having at least 1 KeV energy, directing said ions from a source at an angle greater than zero to a perpendicular to the surface; and d) rotating the surface relative to the source so that the bombardment occurs from different positions relative to the surface, whereby the directing and rotating cause the ions to impact the side walls as well as the top surfaces.
Claim 2
Independent Claim
110 words
A method for processing a semiconductor wafer comprising the steps of: a) applying photoresist to a surface of the wafer; b) patterning the photoresist to create a patterned resist having side walls and top surfaces; c) hardening the patterned photoresist by bombarding the photoresist with ions having at least 1 KeV energy, directing said ions from a source at an angle greater than zero to a perpendicular to the surface; and d) rotating the surface relative to the source so that the bombardment occurs from different positions relative to the surface, whereby the directing and rotating cause the ions to impact the side walls as well as the top surfaces.
Claim 3
Dependent Claim
22 words
A method as recited in claim 1 wherein said ions are a selected species which will not chemically react with said photoresist.
Claim 4
Dependent Claim
22 words
A method as recited in claim 2 wherein said ions are created from gases selected from the group consisting of inert gases.
Claim 5
Dependent Claim
24 words
A method as recited in claim 3 wherein said ions are created from gases selected from the group consisting of noble gases and nitrogen.
Claim 6
Dependent Claim
23 words
A method as recited in claim 4 wherein said ions are created from gases selected from the group consisting of argon and nitrogen.
Claim 7
Dependent Claim
19 words
A method as recited in claim 1 wherein said angle is in the range of 5 to 60 degrees.
Claim 8
Dependent Claim
19 words
A method as recited in claim 6 wherein said angle is in the range of 10 to 45 degrees.
Claim 9
Dependent Claim
19 words
A method as recited in claim 7 wherein said angle is in the range of 20 to 35 degrees.
Claim 10
Dependent Claim
37 words
The method of claim 1, further comprising the step of anisotropically etching the surface of the wafer after the hardening step, whereby the hardened patterned photoresist improves the accuracy of the final etched pattern on the substrate.
Claim 11
Dependent Claim
22 words
A method as recited in claim 9 wherein said ions are a selected species which will not chemically react with said photoresist.
Claim 12
Dependent Claim
22 words
A method as recited in claim 10 wherein said ions are created from gases selected from the group consisting of inert gases.
Claim 13
Dependent Claim
24 words
A method as recited in claim 11 wherein said ions are created from gases selected from the group consisting of noble gases and nitrogen.
Claim 14
Dependent Claim
23 words
A method as recited in claim 12 wherein said ions are created from gases selected from the group consisting of argon and nitrogen.
Claim 15
Dependent Claim
19 words
A method as recited in claim 9 wherein said angle is in the range of 5 to 60 degrees.
Claim 16
Dependent Claim
19 words
A method as recited in claim 14 wherein said angle is in the range of 10 to 45 degrees.
Claim 17
Dependent Claim
19 words
A method as recited in claim 15 wherein said angle is in the range of 20 to 35 degrees.
Claim 18
Dependent Claim
19 words
A method as recited in claim 10 wherein said angle is in the range of 5 to 60 degrees.
Claim 19
Dependent Claim
19 words
A method as recited in claim 17 wherein said angle is in the range of 10 to 45 degrees.
Claim 20
Dependent Claim
19 words
A method as recited in claim 18 wherein said angle is in the range of 20 to 35 degrees.
References Cited (Backward Citations)
US4068018A
Cited
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