| 摘要 |
PROBLEM TO BE SOLVED: To provide a multilayer wiring board and a manufacturing method thereof, wherein a wiring layer equipped with wirings fine and low in resistance can be easily formed on the surface of a glass board a ceramic board, or a metal board at a low cost. SOLUTION: A first process where a soft insulating layer 10 which contains thermosetting resin and has a thermal expansion coefficient difference y of below 100/t<0.4> (wherein t represents the thickness (μm) of a multilayer wiring layer) with a cured base material 17 that is selected out of a glass board, a ceramic board, and a metal board at a temperature range of a room temperature to 300 deg.C is formed on the one primary surface of the mother material 17, a second process where via-holes 11 are provided in the insulating layer 10, and conductor paste is filled into the via-hole 11 to form via-hole conductors 12, and a third process where a wiring circuit layer 14 formed of metal foil previously provided on the surface of a transfer sheet 13 is transferred to the surface of the insulating layer are provided are provided, these processes are repeatedly carried out to form a multilayer wiring layer, and the multilayer wiring layer is bonded together or an insulating layer is repeatedly formed on the surface of the mother material 17, via-hole conductors are provided, a wiring circuit layer is repeatedly formed for the formation of a multilayer wiring layer, and then the multilayer wiring layer is thermally cured by a thermal treatment. |
