| 摘要 |
<p>[Problem] To provide a circuit board with excellent long-term reliability. [Solution] This circuit board has: a ceramic substrate; and a metal plate provided on the ceramic substrate, a metal layer being interposed therebetween. The metal layer comprises a first metal portion contacting the ceramic substrate, a second metal portion contacting the metal plate, and a third metal portion provided between the first metal portion and the second metal portion. Part of the first metal portion extends toward the second metal portion so as to penetrate the third metal portion, and widens in a lateral direction along the second metal portion.</p> |
