| 摘要 |
PROBLEM TO BE SOLVED: To make it easy to mount an electronic component on a circuit board and efficiently radiate heat generated by the electronic component and make it easy to form a through hole in circuit board.SOLUTION: A circuit board 10 comprises: a first insulation layer 1 where mounting regions Ra-Re of electronic components 9a-9e and wiring patterns 5b, 5c, 5e, 5f, 5h are provided on a top face; a metal core 3 provided on an undersurface of the first insulation layer so as to overlap the mounting region Ra, Rb, Rd in a vertical direction; and a second insulation layer 2 provided on the undersurface of the first insulation layer 1 and around the metal core 3. An undersurface of the metal core 3 is exposed from the second insulation layer 2 and heat conductivity of each of the first insulation layer 1 and the metal core 3 is higher than heat conductivity of the second insulation layer 2, and hardness of the first insulation layer 1 is higher than hardness of the second insulation layer 2. In the circuit board 10, through holes 6b, 6c, 6e which pierce the insulation layers 1, 2 to connect the wiring patterns in the insulation layers 1, 2 are provided.SELECTED DRAWING: Figure 2 |
