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:
Mar. 15, 2022
Filed:
May. 29, 2018
Denka Company Limited, Tokyo, JP;
Akimasa Yuasa, Omuta, JP;
Yusaku Harada, Omuta, JP;
Takahiro Nakamura, Omuta, JP;
Shuhei Morita, Omuta, JP;
Kouji Nishimura, Omuta, JP;
DENKA COMPANY LIMITED, Tokyo, JP;
Abstract
A ceramic circuit substrate having a metal plate bonded, by a bonding braze material, to at least one main surface of a ceramic substrate, wherein the bonding braze material contains, as metal components, 0.5 to 4.0 parts by mass of at least one active metal selected from among titanium, zirconium, hafnium, and niobium, with respect to 100 parts by mass, in total, of 93.0 to 99.4 parts by mass of Ag, 0.1 to 5.0 parts by mass of Cu, and 0.5 to 2.0 parts by mass of Sn; and Cu-rich phases in a bonding braze material layer structure between the ceramic substrate and the metal plate have an average size of 3.5 μm or less and a number density of 0.015/μm2 or higher. A method for producing a ceramic circuit substrate includes bonding at a temperature of 855 to 900° C. for a retention time of 10 to 60 minutes.