| 摘要 |
PROBLEM TO BE SOLVED: To prevent the occurrence of cracks in a board, which is induced by means of thermal stress caused by thermal expansion difference between the head radiation circuit board and a low resistance conductor, and the developing of the cracks and to prevent the disconnection of a wiring conductor between the low resistance conductor, in a heat radiation circuit board and the board. SOLUTION: A low resistance conductor 2 formed of molybdenum or tungsten is jointed on a ceramic board 1, formed of an aluminium nitride sintered body, a silicon nitride sintered body or a silicon carbide sintered body as a semiconductor device loading part. Then, a heat radiation circuit board is formed by installing the metal body of at least more than one type selected from among molybdenum, tungsten, copper, aluminium and silver on the ceramic board 1 as a bus bar part 3. |
