摘要 |
According to the present invention, a circuit board for mounting electronic components including a metal layer united with a substrate layer with a predetermined portion of the metal layer exposed is manufactured by disposing a mask between a substrate layer and a metal layer where the metal layer is to be exposed and uniting the substrate layer and the metal layer with the mask therebetween, projecting a laser beam onto the substrate layer at the periphery of the mask to cut away the substrate layer adjacent to the mask, and stripping off that part of the substrate layer which remains on the mask and the mask. |