| 摘要 |
PROBLEM TO BE SOLVED: To achieve stable electric connection between a conductive circuit and a conductive resin with low resistance, in a circuit board formed by provid ing the conductive circuits on both front and rear surfaces of an insulated substrate, and connecting the conductive circuits to each other with the conduc tive resin through a through hole formed in the insulated substrate. SOLUTION: The conductive circuit provided to the insulated substrate comprises a groove. The groove and the through hole are filled with the conductive resin to increase an area of a contact surface between the conductive circuit and the conductive resin. Thereby the electrical connection of them is absolutely obtained and resistance is lowered. To form the groove to the conductive circuit, a resist pattern whose width is sufficiently smaller than the thickness of the conductive circuit is used for alkali-etching. COPYRIGHT: (C)2004,JPO |
