← Back to Patent Explorer
US4340654A Expired / Lapsed US ⏱️ 0.0 years remaining

Defect-free photomask

Assignee: Individual
•
Filing: 1981-06-18
•
Granted: 1982-07-20
•
Expires: 2001-06-18
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A process for forming a defect-free photomask consisting of an opaque layer overlying a substrate transparent to radiant energy and which comprises applying a coating material which absorbs radiant energy to the surface of a substrate, directing a beam of radiant energy through the substrate onto the coating material so as to fuse the coating material and the substrate at their interface thereby forming an opaque layer on said substrate, and removing from the surface the unfused coating material.

Inventors

  • 👤 James G. Campi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 12:40
CPC Classifications
G; G03; G03F; G03F1/00; G03F1/68; G03F1/72; Y; Y10; Y10S; Y10S430/00; Y10S430/146

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 113 words
A process for repairing transparent defects in a photomask consisting of a defect containing opaque layer overlying a substrate which is transparent to radiant energy, comprising: applying a coating material which absorbs radiant energy to the opaque layer and over the transparent defect; directing a beam of radiant energy through the substrate and onto said coating in the defect areas, said beam containing sufficient radiant energy to fuse the material at the interface of the substrate and the coating material such that the fusing operation forms a layer of an opaque mixture obscuring the defect area thereby eliminating the defect in the photomask; and removing from the photomask surface the unfused coating material.
Claim 2
Dependent Claim 113 words
A process for repairing transparent defects in a photomask consisting of a defect containing opaque layer overlying a substrate which is transparent to radiant energy, comprising: applying a coating material which absorbs radiant energy to the opaque layer and over the transparent defect; directing a beam of radiant energy through the substrate and onto said coating in the defect areas, said beam containing sufficient radiant energy to fuse the material at the interface of the substrate and the coating material such that the fusing operation forms a layer of an opaque mixture obscuring the defect area thereby eliminating the defect in the photomask; and removing from the photomask surface the unfused coating material.
Claim 3
Dependent Claim 18 words
The process as recited in claim 1 wherein said fused interface is at least 400 A in thickness.
Claim 4
Dependent Claim 9 words
The product made by the process of claim 2.
Claim 5
Dependent Claim 79 words
A process for forming a defect-free photomask overlying a substrate transparent to a beam of radiant energy, comprising: applying to a surface of a transparent substrate a coating material which absorbs radiant energy; directing a beam of radiant energy through said substrate and onto said coating material in a predetermined pattern so as to fuse the materials at the coating/substrate interface and form an opaque mixture defining said photomask; and removing from the substrate surface the unfused coating material.
Claim 6
Dependent Claim 79 words
A process for forming a defect-free photomask overlying a substrate transparent to a beam of radiant energy, comprising: applying to a surface of a transparent substrate a coating material which absorbs radiant energy; directing a beam of radiant energy through said substrate and onto said coating material in a predetermined pattern so as to fuse the materials at the coating/substrate interface and form an opaque mixture defining said photomask; and removing from the substrate surface the unfused coating material.
Claim 7
Dependent Claim 9 words
The product made by the process of claim 4.

References Cited (Backward Citations)

US3089732A Cited
US3873339A Cited
US4122240A Cited
US4142892A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1985-07-19 1986-01-18 1986-07-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1989-07-19 1990-01-18 1990-07-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1993-07-19 1994-01-18 1994-07-20 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag