| 摘要 |
PROBLEM TO BE SOLVED: To eliminate the need for heating the circuit board of a hybrid integrat ed circuit by omitting Au thin wires and Au coatings by coating a first electrode on the circuit board side and a second electrode on a flexible sheet side with Ni and connecting metallic wires composed of the coating Ni and Al to each other by wire bonding. SOLUTION: Cu patterns 14, 18, and 20 are formed on the circuit board 11 of a hybrid integrated circuit insulated with an insulating material 12. Then the surface of the circuit board 11 is coated with a resist film 41 having a rectangular window 40 and electroplating is performed. After electroplating, Ni coatings 42 are formed on pads 20 by impressing voltages upon wires 18 so as to make electric currents flow. In addition, a flexible sheet is stuck to the board 11 with an adhesive. Finally, Al thin wires are bonded after the adhesive is cured. Therefore, the wire bonding of the Al thin wires becomes possible at a room temperature and the bondability of the thin wires can be improved, because the flexible sheet itself can prevent the softening of the underlying adhesive. |
