| 摘要 |
PROBLEM TO BE SOLVED: To provide a highly reliable circuit board and an electronic device in which cracking of an insulating base or peeling of a copper plate due to thermal stress, caused by thermal expansion difference between the copper plate and the insulating base at the end of a metal plate, is prevented.SOLUTION: In a circuit board 1 having an insulating base 3, and a metal plate 2 bonded onto the insulating base 3, the metal plate 2 has a first copper plate 2a provided on the bonding surface to the insulating base 3, a second copper plate 2b provided on the outer surface, and a low thermal expansion plate 2c provided between the first copper plate 2a and second copper plate 2b. The ratio of the volume of the low thermal expansion plate 2c to the volume of the copper plate at the end A of the metal plate 2 is larger than that in the center B of the metal plate 2. |
