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:
Dec. 25, 2018
Filed:
Jul. 27, 2016
Kabushiki Kaisha Toshiba, Tokyo, JP;
Toshiba Materials Co., Ltd., Yokohama-Shi, Kanagawa-Ken, JP;
Hiromasa Kato, Nagareyama Chiba, JP;
Noboru Kitamori, Miura Kanagawa, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Toshiba Materials Co., Ltd., Kanagawa-Ken, JP;
Abstract
The present invention provides a silicon nitride circuit board in which metal plates are attached on front and rear sides of a silicon nitride substrate having a three-point bending strength of 500 MPa or higher, with attachment layers interposed therebetween, wherein assuming that a thickness of the metal plate on the front side is denoted by t, and a thickness of the metal plate on the rear side is denoted by t, at least one of the thicknesses tand tis 0.6 mm or larger, a numerical relation: 0.10≤|t−t|≤0.30 mm is satisfied, and warp amounts of the silicon nitride substrate in a long-side direction and a short-side direction both fall within a range from 0.01 to 1.0 mm. Due to above configuration, TCT properties of the silicon nitride circuit board can be improved even if the thicknesses of the front and rear metal plates are large.