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:
Jan. 10, 1989
Filed:
Feb. 17, 1988
Yoichi Nakamura, Hiratsuka, JP;
Shirushi Yamamoto, Isehara, JP;
Takashi Komine, Yokohama, JP;
Akira Yokota, Yamato, JP;
Hisashi Nakane, Kawasaki, JP;
Tokyo Ohka Kogyo Co., Ltd., Kanagawa, JP;
Abstract
A dually photosensitive composition useful as a photoresist in the manufacture of ICs and the like electronic devices, which is positively photosensitive by exposure to ultraviolet in a relatively small dose but negatively photosensitive by exposure to ultraviolet in a substantially larger dose than above or by exposure to far ultraviolet light, is obtained by admixing a positive-type photoresist material comprising a novolac resin and an o-naphthoquinone diazide compound with a bisazide compound such as 4,4'-diazidodiphenyl sulfide. The inventive photosensitive composition provides a possibility of developing an ingenious technique for patterning of a photoresist layer on the substrate such as a checkboard-like patterned layer by use of a photomask of a line-and-space pattern.