| 摘要 |
PROBLEM TO BE SOLVED: To provide a highly reliable cracking-free ceramic substrate wherein no thermal stress concentration due to difference in thermal expansion occurs at the junction between a ceramic substrate and an active brazing metal even under repeated thermal impacts inflicted after the bonding of the ceramic substrate and a metal circuit board by the active brazing metal. SOLUTION: The ceramic circuit board comprises a ceramic substrate 1 and a metal circuit board 2 made of copper or a copper alloy which is bonded by an active brazing metal 3 to the top surface of the ceramic substrate 1. Just under the edge of the active brazing metal 3 which is above the top surface of the ceramic substrate 1, a groove in the ceramic substrate 1 and a unbonded region 5 which is free of the active brazing metal 3 are in presence along a bonded edge A, wherein an opening extends from a location facing a bonded edge B formed between the metal circuit board 2 and the active brazing metal 3 to a bonded edge A formed between the ceramic substrate 1 and the active brazing metal 3, with the bonded edge A located further inside the bonded edge B. COPYRIGHT: (C)2004,JPO&NCIPI |
