EP0087582A2
Expired / Lapsed
EP
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Optical lithography process for creating patterns in a silicon semiconductor substrate
Assignee: International Business Machines Corp
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Filing: 1983-01-26
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Granted: —
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Expires: 2003-01-26
Abstract
Abstract The invention relates to an optical lithography process for creating patterns in a silicon semiconductor substrate. The improved resolution, as used in the very large scale integration of electronic circuits, is obtained by employing a thin film of 4-phenylazo-1-naphthylamine between the silicon substrate and the overlying layer of a light sensitive photoresist. The 4-phenylazo-1-naphthylamine acts as a stable, highly light absorbent medium exhibiting chemical and physical compatibility with the silicon substrate and photoresists with ether-type solvent systems.
Inventors
- 👤 Leon H. Kaplan
- 👤 Richard Dean Kaplan
- 👤 Steven Michael Zimmerman
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 14:33
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/004; G03F7/09; G03F7/091
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
78 words
Optical lithography process for creating patterns in a silicon semiconductor substrate, characterized in that Sudan Black B dyestuff is evaporated upon said silicon substrate to form a thin film principally the compound 4-phenylazo-1-naphthylamine; positive resists having ether-type solvents are deposited on said 4-phenylazo-1-naphthylamine thin film; and selected regions of said positive resist are exposed to light whereby said 4-phenylazo-1-naphthylamine thin film acts to absorb said light and prevent reflection and scattering from the surface of said silicon substrate.
Claim 2
Dependent Claim
78 words
Optical lithography process for creating patterns in a silicon semiconductor substrate, characterized in that Sudan Black B dyestuff is evaporated upon said silicon substrate to form a thin film principally the compound 4-phenylazo-1-naphthylamine; positive resists having ether-type solvents are deposited on said 4-phenylazo-1-naphthylamine thin film; and selected regions of said positive resist are exposed to light whereby said 4-phenylazo-1-naphthylamine thin film acts to absorb said light and prevent reflection and scattering from the surface of said silicon substrate.
Claim 3
Dependent Claim
31 words
Process as set forth in claim 1, characterized in that the step of evaporating Sudan Black B dyestuff involves evaporating at a temperature of at least 120°C for approximately 5 minutes.
Claim 4
Dependent Claim
32 words
Process as set forth in claim 1, characterized in that said substrate is baked at a temperature of at least 160°C for approximately 10 minutes after said 4-phenylazo-l-naphthylamine thin film is evaporated.
Claim 5
Dependent Claim
27 words
Process as set forth in claim 1, characterized in that the step of exposing selected regions of said positive resist to light involves exposing to UV light.
Claim 6
Dependent Claim
34 words
Process as set forth in claim 1, characterized in that the step of evaporating Sudan Black B dyestuff involves evaporating at a pressure between 1.33 x 10 -6 and 1.33 x 10 -7 bar.
Claim 7
Dependent Claim
29 words
Process as set forth in claim 1, characterized in that the positive resists have ether-type solvent systems such as diglycol methyl ether, ethyl glycol acetate or methyl glycol acetate.
Claim 8
Dependent Claim
17 words
Process as set forth in claim 1, characterized in that the positive resists include sensitized novolak resins.
Claim 9
Dependent Claim
23 words
Process as set forth in claims 1 and 4, characterized in that the light is in the 250 to 440 nm wavelength range.
References Cited (Backward Citations)
No citation records indexed.
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