| 摘要 |
PURPOSE:To retard the generation of plating voids by carrying forward liquid treatment step after boring while imparting vibration to a board to be processed. CONSTITUTION:A wiring adhesive 3 is pressed onto an inner layer circuit board and a conductive wire 1 coated with an insulating layer 2 is laid thereon. Prepregs 4 and outer layer copper foils 5 are then pressed thereon followed by drilling, electroless plating, and formation of surface circuit thus producing a multiwire wiring board. In this regard, during liquid treatment process after drilling before finish of electroless plating, vibration is imparted continuously or intermittently to the board when it is treated at least with alkaline permanganate neutralization liquid in hole cleaning step, and degreasing/conditioning liquid, catalyst imparting liquid or electroless plating liquid in pretreatment step for electroless plating. This method eliminates plating voids or thin plating from through hole wire part and produces a multiwire wiring board having excellent wire joints. |
