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:
May. 23, 1989
Filed:
Sep. 19, 1988
Hatsuyuki Tanaka, Samukawa, JP;
Hidekatsu Kohara, Chigasaki, JP;
Yoshiyuki Sato, Samukawa, JP;
Shingo Asaumi, Fujisawa, JP;
Toshimasa Nakayama, Hiratsuka, JP;
Akira Yokota, Yamato, JP;
Hisashi Nakane, Yokohama, JP;
Tokyo Ohka Kogyo Co., Ltd., Kawasaki, JP;
Abstract
The aqueous developing solution of the invention for positive-working photoresist compositions contains, in addition to an organic basic compound free from metallic ions, such as tetramethyl ammonium hydroxide and choline, as the principal ingredient, from 50 to 5000 ppm of an acetylene alcohol. In comparison with conventional developing solutions, the inventive developing solution is advantageous in the uniformity of the patterned photoresist layer, higher sensitivity and smaller temperature dependency of development and less drawbacks due to foaming of the solution.