| 摘要 |
<p>A ceramic circuit board is characterized by being constituted by bonding a ceramic substrate 2 and a metal circuit plate 3 to each other through a silver-copper-based brazing material layer 5 containing at least one active metal selected from Ti, Zr, Hf, V, Nb and Ta, and wherein the Vickers hardness of a reaction product layer 6 generated by causing the silver-copper-based brazing material layer 5 and the ceramic substrate 2 to react with each other is 1,100 or more. At least one element selected from In, Zn, Cd, and Sn is preferably contained in the silver-copper-based brazing material layer 5. Further, 0.1 to 10.0 wt% of carbon powder is preferably contained in the brazing material layer 5. According to the above arrangement, there can be provided a ceramic circuit board in which cracks are effectively suppressed from being formed even after a thermal cycle is repeatedly applied for a long period of time, i.e., a ceramic circuit board having so-called excellent heat-cycle resistance characteristics and high reliability. <IMAGE></p> |
