| 摘要 |
PURPOSE:To reduce the warpages of a ceramic board and an insulating layer and to stabilize the mounting of a component by laminating an insulating layer having larger thermal expansion coefficient and an insulating layer having smaller thermal expansion coefficient than that of the ceramic board on the ceramic board. CONSTITUTION:A conductor interconnection 5 is formed on a ceramic board 1, two first insulating layers 2 having larger thermal expansion coefficient than that of the ceramic board 1 are laminated, one second insulating layer 3 having smaller thermal expansion coefficient than that of the ceramic board 1 and having a conductor interconnection 5 thereon is laminated thereon, and one first insulating layer 2 and a protective film 4 are further formed on the second insulating layer 3. With this construction, a force for generating a warpage in a recess direction and a force for generating a warpage in a protruding direction are balanced to prevent the whole thick film board from warping. |
