| 摘要 |
PROBLEM TO BE SOLVED: To remove residual water on an insulating substrate so as to improve insulation of the substrate and adhesion of a conductive circuit, by preventing air bubbles whose internal diameter is a fixed value or more in an adhesive layer according to an annealing operation performed before-making a rough surface. SOLUTION: An adhesive layer 3, which is used for electroless plating with a rough surface, is formed on an insulating substrate 1. A conductive circuit 7 is formed thereon. Subsequently, air bubbles with an internal diameter of 5μm or more are prevented in the adhesive layer 3 according to an annealing operation, which is performed before making a rough surface. A peeling strength is set at 1.5 kgf/cm or more between the adhesive layer 3 and the conductive circuit 7. With the annealing operation, the insulating substrate 1 is dried and residual water is removed on the substrate 1. It is possible to positively prevent a number of large air bubbles from appearing in the adhesive layer 3. Thus, the exfoliation of the conductive circuit 7 can be prevented that is caused by reduction in insulation of the substrate 1, a change in size of the substrate 1, and reduction in anchor effect. |
