| 摘要 |
PROBLEM TO BE SOLVED: To provide a circuit wiring board capable of satisfying electrical connecting reliability. SOLUTION: The circuit wiring board comprises a metal layer 2 having a plurality of first through holes 2a formed at a predetermined interval in a thickness direction, insulating resin layers 3 made of insulating resins laminated on both side surfaces of the layer 2 to cover both side surfaces of the layer 2 by heating and pressurizing and to close inner peripheral surfaces of the first through holes 2a, and electrical circuit wirings 4 formed on both side surfaces of the layers 3. Second through holes 1a smaller than the first holes 2a are substantially concentrically provided at a part of the layer 3 for closing the holes 2a, and the wirings 4 formed on both side surfaces of the layer 3 are conducted by utilizing the holes 1a. An elastic modulus of the insulating layer is 7 MPa or less at a temperature for laminating, heating and pressurizing. |
