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:
Sep. 12, 1989
Filed:
Oct. 27, 1987
Noboru Yamaguchi, Kadoma, JP;
Satoru Ogawa, Kadoma, JP;
Susumu Kajita, Kadoma, JP;
Izuru Yoshizawa, Kadoma, JP;
Kiyotaka Waki, Kadoma, JP;
Masayuki Ishihara, Kadoma, JP;
Matsushita Electric Works, Ltd., Osaka, JP;
Abstract
A method for roughening a ceramic substrate surface includes a step of sequentially taking out part of roughening a treatment bath of phosphoric acid into which the ceramic substrate is dipped prior to a formation on the substrate of conductor a layer, and subjecting the part of the bath taken out sequentially to regeneration treatment. Any increase in the viscosity due to dehydrating condensation of the roughening bath can be thereby effectively restrained to prolong effective life of the bath. Further, the surface roughened ceramic substrate can be provided thereon with conductor layers smoothly formed by means of a plating and eventually with a circuit pattern as well as a resistor formed on the pattern within an inert gas atmosphere.