| 摘要 |
<p>PURPOSE:To prevent a circuit pattern from damaging due to heat for a long period by forming a platinum- or palladium-plated layer having a specific thickness on the surface of a circuit pattern copper foil used for a resin board. CONSTITUTION:Platinum or palladium of at least 0.5 micron or more of thickness is electroplated on a circuit pattern 4 of each board. Tin, lead, eutectic solder cream are printed, and heated to form solder bumps 5. An electric component 7 is secured in advance on the same plane as the circuit pattern through resin, etc., in the hole of the board, and adhering solder bumps are formed similarly to the other solder bumps. In order to provide positional relation of the boards, the solders are melted by pressurizing and heating through a jig, etc., and the boards are laminated. Liquid epoxy resin 6 is immersed in air gaps between the boards, and cured to complete the board.</p> |
