| 摘要 |
<p>PURPOSE:To reduce the area of a circuit board occupied by resistors and realize the high mounting-density circuit board by a method wherein the resistors are formed in the through-holes of the board. CONSTITUTION:Resistance paste 14 is applied to the surface of a board 1 by printing and baked to form resistors 4 in the through-holes 12 of the board 1. On the other hand, conductive layers 15 are provided on both the sides of the board 1 and the conductive layer 15 on the one side of the board 1 is electrically connected to the conductive layer 15 on the other side with the resistors 4. After that, the unnecessary parts of the conductive layers 15 are removed by etching to form wiring patterns 5. Gold paste is applied to the predetermined positions of the wiring patterns 5 by printing and dried and baked to provide gold electrodes 2. The surface of the wiring patterns 5 except component mounting parts are covered with solder resist material 13. Then a bare chip IC 6 is bonded to the board 1 and connected to the gold electrodes 2 with bonding wires 7. A resin coating film 8 is formed by potting. With this constitution, the high mounting-density circuit board can be realized.</p> |
