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US4523974A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of fabricating a pellicle cover for projection printing system

Assignee: SVG LITHOGRAPHY Inc A CORP OF
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Filing: 1984-03-21
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Granted: 1985-06-18
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Expires: 2004-03-21
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Abstract

Abstract The invention is also directed to a method of fabricating a pellicle cover assembly for use in a projection printing system for forming an image on a radiation sensitive wafer, the method comprising the steps of applying a gold film onto the surface of a wafer, applying a polymer film onto the gold film surface, curing the polymer film, adhering a support ring to the polymer film, cutting through the polymer and gold films between the ring and wafer edges to expose the wafer surface, peeling the ring off the wafer and etching off the gold film.

Inventors

  • 👤 Dawn L. Duly
  • 👤 Henry Windischmann
  • 👤 W. D. Buckley

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 06:55
CPC Classifications
G; G03; G03F; G03F1/00; G03F1/62; G03F1/64

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 113 words
A method of fabricating a pellicle cover assembly for use in a projection system for forming an image on a radiation sensitive wafer, said method comprising the steps of: applying a gold film onto the surface of a wafer; applying a thin uniform polymer film onto the gold film surface of said wafer; curing said polymer film; adhering a pellicle support ring to the polymer film; cutting through the polymer and gold films between the ring and wafer edges to expose the wafer surface; carefully peeling the ring off the wafer, resulting in a gold coated polymer membrane that is already mounted on a pellicle support ring; and etching off the gold film.
Claim 2
Independent Claim 113 words
A method of fabricating a pellicle cover assembly for use in a projection system for forming an image on a radiation sensitive wafer, said method comprising the steps of: applying a gold film onto the surface of a wafer; applying a thin uniform polymer film onto the gold film surface of said wafer; curing said polymer film; adhering a pellicle support ring to the polymer film; cutting through the polymer and gold films between the ring and wafer edges to expose the wafer surface; carefully peeling the ring off the wafer, resulting in a gold coated polymer membrane that is already mounted on a pellicle support ring; and etching off the gold film.
Claim 3
Dependent Claim 20 words
A method of fabricating a pellicle cover assembly according to claim 1 wherein said wafer is an oxidized silicon wafer.
Claim 4
Dependent Claim 23 words
A method of fabricating a pellicle cover assembly according to claim 1 wherein the gold film has a thickness of about 500 angstroms.
Claim 5
Dependent Claim 31 words
A method of fabricating a pellicle cover assembly according to claim 1 wherein said step of coating a thin polymer film onto the surface of the wafer uses a spinning process.
Claim 6
Dependent Claim 32 words
A method of fabricating a pellicle cover assembly according to claim 1 wherein said step of curing the polymer film is effected in an oven at a temperature of about 170° C.
Claim 7
Dependent Claim 28 words
A method of fabricating a pellicle cover assembly according to claim 1 wherein said step of etching off the gold is effected with a solution of potassium iodide.
Claim 8
Dependent Claim 25 words
A method of fabricating a pellicle cover assembly according to claim 1 wherein said step of applying a gold film is effected by vacuum evaporation.
Claim 9
Dependent Claim 18 words
A method of fabricating a pellicle cover assembly according to claim 1 wherein said polymer film is polymethymethacrylate.
Claim 10
Independent Claim 150 words
A method of fabricating a pellicle cover assembly for use in a projection system for forming an image on a radiation sensitive wafer, said method comprising the steps of: applying a gold film of about 500 angstroms thickness onto the surface of an oxidized silicon wafer by vacuum evaporation; coating a thin uniform polymer film of polymethylmethacrylate onto the gold film surface of said wafer using a spinning process; curing said polymer film in an oven at a temperature of about 170° C.; epoxying a pellicle support ring to the polymer film; cutting around the ring between the ring and the wafer edges through the polymer and gold films so that the wafer surface is exposed; peeling the ring off the wafer resulting in a gold coated polymer membrane that is already mounted on a pellicle support ring; and etching off the gold film with a solution of hydrogen iodide.
Claim 11
Independent Claim 150 words
A method of fabricating a pellicle cover assembly for use in a projection system for forming an image on a radiation sensitive wafer, said method comprising the steps of: applying a gold film of about 500 angstroms thickness onto the surface of an oxidized silicon wafer by vacuum evaporation; coating a thin uniform polymer film of polymethylmethacrylate onto the gold film surface of said wafer using a spinning process; curing said polymer film in an oven at a temperature of about 170° C.; epoxying a pellicle support ring to the polymer film; cutting around the ring between the ring and the wafer edges through the polymer and gold films so that the wafer surface is exposed; peeling the ring off the wafer resulting in a gold coated polymer membrane that is already mounted on a pellicle support ring; and etching off the gold film with a solution of hydrogen iodide.
Claim 12
Independent Claim 82 words
A method of fabricating a pellicle cover assembly for use in a projection printing system for forming an image on a radiation sensitive wafer, said method comprising the steps of: applying a thin gold film onto a chromium coated surface of a silicon wafer, applying a thin uniform polymer film onto the gold film surface of said wafer, curing said polymer film, adhering a pellicle support ring to the polymer film; and carefully peeling the polymer film directly off the gold surface.
Claim 13
Independent Claim 82 words
A method of fabricating a pellicle cover assembly for use in a projection printing system for forming an image on a radiation sensitive wafer, said method comprising the steps of: applying a thin gold film onto a chromium coated surface of a silicon wafer, applying a thin uniform polymer film onto the gold film surface of said wafer, curing said polymer film, adhering a pellicle support ring to the polymer film; and carefully peeling the polymer film directly off the gold surface.
Claim 14
Dependent Claim 18 words
A method of fabricating a pellicle cover assembly according to claim 10 wherein said polymer film is polymethylmethacrylate.
Claim 15
Dependent Claim 23 words
A method of fabricating a pellicle cover assembly according to claim 10 wherein said gold film has a thickness of about 500 angstroms.
Claim 16
Dependent Claim 24 words
A method of fabricating a pellicle cover assembly according to claim 10 wherein said step of applying a polymer film uses a spinning process.
Claim 17
Dependent Claim 32 words
A method of fabricating a pellicle cover assembly according to claim 10 wherein said step of curing the polymer film is effected in an oven at a temperature of about 170° C.
Claim 18
Dependent Claim 25 words
A method of fabricating a pellicle cover assembly according to claim 10 wherein said step of applying a gold film is effected by vacuum evaporation.

References Cited (Backward Citations)

US4058432A Cited
US4170512A Cited
US4384919A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-06-17 1988-12-17 1989-06-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-06-17 1992-12-17 1993-06-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-06-17 1996-12-17 1997-06-18 $7700.00 Window Closed / Lapsed

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