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. 01, 2002
Filed:
Apr. 22, 1999
Tsutomu Hashizume, Nagano, JP;
Seiko Epson Corporation, Tokyo, JP;
Abstract
In a method of making an ink jet recording head, oxide films are formed on both surfaces of a silicon substrate, followed by a first metal film, a piezoelectric film, and a second metal film. A positive resist is formed on the bottom of the substrate, and a first negative resist on the top over the second metal film. The substrate is exposed between two masks. The positive resist is developed first with an alkaline solvent, and then the negative resist is developed with an organic solvent. A second negative resist is formed on top of the substrate before the bottom is etched with the patterned positive resist. The second negative resist is removed afterward, and then the second metal film is etched using the patterned first negative resist.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile