§
Luxuse
Patent Intelligence
Sign In
← Back to Patent Explorer
EP0209152A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

Pre-exposure method for increased sensitivity in high contrast resist development

Assignee: Shin Etsu MicroSi Inc
•
Filing: 1986-07-18
•
Granted: —
•
Expires: 2006-07-18
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A high contrast developing process is described for use after pre-exposure to UV-visible radiation to produce increased sensitivity during lithographic processing of positive resists layers. Compared to samples which have not been subjected to the methods of this invention, sensitivity increases of a factor of 2-4 are to be expected. An additional benefit of low film loss from unexposed resist is obtained. The system disclosed is applicable to lithographic exposures utilizing electrons, photons (eg. UV-visible, x-rays, etc.) and atomic or molecular charged particles. Specifically, as a result of the increased sensitivity, higher throughput during lithographic processing for the fabrication of photomasks and semiconductor devices is realized.

Inventors

  • 👤 Robert Austin Owens
  • 👤 Roland Lee Chin
  • 👤 Susan Antoinette Ferguson
  • 👤 James Marvin Lewis

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-04 10:05
CPC Classifications
G; G03; G03C; G03C5/00; G03C5/18; G03F; G03F7/00; G03F7/20; G03F7/2022; G03F7/26

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 69 words
A process for developing radiation sensitive film comprising: (a) pre-exposing the film under controlled conditions that permit substantially maximum exposure of the film to a point short of significant film loss, (b) subjecting the pre-exposed film of step (a) to normal exposure with optical or electron beam radiation, and (c) contacting the exposed film with a high contrast aqueous alkaline developer solution until the film is substantially fully developed.
Claim 2
Dependent Claim 69 words
A process for developing radiation sensitive film comprising: (a) pre-exposing the film under controlled conditions that permit substantially maximum exposure of the film to a point short of significant film loss, (b) subjecting the pre-exposed film of step (a) to normal exposure with optical or electron beam radiation, and (c) contacting the exposed film with a high contrast aqueous alkaline developer solution until the film is substantially fully developed.
Claim 3
Dependent Claim 15 words
The process of claim 1 in which the film is exposed to ultraviolet visible radiation.
Claim 4
Dependent Claim 16 words
The process of claim 1 in which the pre-exposed film is exposed by electron beam radiation.
Claim 5
Dependent Claim 50 words
The process of claim 1 in which the pre-exposure is effected by UV and/or visible radiation, the subsequent normal exposure is effected with UV/visible radiation, X-ray or a beam of atomic or molecular charged particles, and the development of the film is effected with a high contrast aqueous alkaline developer.
Claim 6
Dependent Claim 23 words
The process of claim 4 in which the film that is subjected to pre-exposure, normal exposure and development is a radiation sensitive film.
Claim 7
Dependent Claim 17 words
The process of claim 4 in which the film subjected to pre-exposure is a photosensitive resist film.
Claim 8
Dependent Claim 12 words
The process of claim 4 in which the developer comprises potassium hydroxide.
Claim 9
Dependent Claim 12 words
The process of claim 4 in which the developer comprises sodium hydroxide.
Claim 10
Dependent Claim 12 words
The process of claim 4 in which the developer comprises sodium silicate.

References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Maintenance schedule is calculated for granted US utility patents.

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag