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:
Apr. 17, 1984
Filed:
Jun. 09, 1982
Applicant:
Inventors:
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C23F / ; H05K / ;
U.S. Cl.
CPC ...
156656 ; 156664 ; 252 792 ; 427130 ; 29603 ; 430318 ;
Abstract
In forming a magnetic film pattern of permalloy by photoetching, the permalloy magnetic film formed on a substrate is etched in an etching solution containing ferric chloride, hydrochloric acid and phosphoric acid, thereby gradually reducing the thickness of the film pattern at the side edges in a tapered state. The permalloy magnetic film can be easily taper-etched without any deterioration of magnetic properties of permalloy magnetic film and substrate surface, but with a greatly improved yield of magnetic film head production and a greatly improved reliability.