| 摘要 |
PROBLEM TO BE SOLVED: To enhance adhesion between a wiring pattern layer and a substrate and insulation performance between wiring pattern by employing an insulation resin layer formed from hardening a polyimide layer containing solvent soluble polyimide. SOLUTION: Each wiring pattern layer 3-5 has a conductive layer 3a-5a and an underlying insulating resin layer 3b-5b. At a part where respective wiring pattern layers intersect or overlap, the wiring pattern layers are surely insulated by insulating resin layer 4b, 5b composing the overlying wiring pattern layers. The insulating resin layer 3b-5b are formed by hardening a polyimide layer containing solvent soluble polyimide. According to the structure, adhesion is enhanced between the substrate and the insulating resin layer and between the wiring pattern layer and the insulating resin layer. Furthermore, the heat resistance and electrical insulation of the insulating resin layer constituting each overlying wiring pattern layer are enhanced. |
