| abstract |
A metallic base board is used for mounting electronic components thereon. The board is formed by laminating a plurality of copper foils on a metallic board through thermoplastic polyimide. On the copper foils circuit patterns are formed. The metallic base board having such circuit patterns is bent and deeply drawn in order to configure a box having an open face. The area of the open face is nearly equal to that of the bottom face. On the edges of the open face flanges are formed. On the flanges, by patterning, there are formed leads which are used for connecting this board to another wiring board. The three-dimensional printed circuit board thus prepared is mounted on another wiring board with its open face down. The leads are soldered to the circuit pattern on the wiring board. Electronic components are mounted on the bottom face of the three-dimensional printed circuit board. Hence, an electronic circuit package is constructed. |