| 摘要 |
PURPOSE:To facilitate fitting of a chip carrier to a wiring substrate by a method wherein a projecting part or a recess part is provided to the back of the chip carrier, while a recess part or a projecting part to be engaged therewith is provided to the surface of the wiring substrate to be assembled with the chip carrier. CONSTITUTION:A projecting part 11 is provided to the back of a ceramic base 1, the projecting part 11 thereof is fitted in a recess part 12 provided on the surface of a wiring substrate 5, and the relative position of both can be matched surely according thereto. At this time, by making depth (d) of the recess part 12 to be a little shallower than height (h) of the projecting part 11, thickness of a solder layer 6 at mounting completed time can be set properly, and sure adhesion can be attained. Moreover, because the projecting part 11 and the recess part 12 can be fitted to attain contact sufficiently, developed heat on the chip carrier side is transmitted efficiently to the wiring substrate 5, a substrate body which is so called as a mother board for example, and heat dissipation is improved, too. |
