The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 21, 1989
Filed:
Jan. 21, 1988
Shinya Katoh, Tokyo, JP;
Fujitsu Limited, Kanagawa, JP;
Abstract
A negative type electron beam sensitive resist film of CMS (chloro-methyl poly-styrene) is developed in a dry environment without using a vacuum system. The resist film is selectively exposed to an electron beam to form a latent image of a desired pattern therein and, then, subjected to irradiation by deep UV having a spectral component of 2537 .ANG. or shorter in an oxidizing gas such as atmospheric air. The average thickness decrease speeds during the dry development are 12 .ANG./min and 300 .ANG./min respectively for the portions exposed and unexposed to the electron beam, revealing a contrast ratio of 100 to 4 in terms of the remaining resist film thickness. A film of PGMA (poly-glycidyl metha-acrylate), and other negative type electron beam sensitive resists, may also be developed by the same method.