| 摘要 |
PURPOSE: To improve a yield of a controlled impedance of a flexible circuit by using a conductive adhesive as a side rise grounding face of a flexible substrate on the opposite side to a trace pattern and as a material for forming an electric channel passing through the flexible substrate. CONSTITUTION: Through holes 26, 28 and 30 are formed in a flexible substrate 10. A pattern of a trace 32 has a lead inner end part 34 formed in the type of a cantilever extending from the flexible substrate 10. A conductive adhesive 36 is applied on the surface of the flexible substrate 10 on the opposite side to the grounding trace 32. This conductive adhesive is applied suitably by using a screen printing method. The conductive adhesive covers the rear of the flexible substrate. Besides, the conductive adhesive also penetrates into the through holes and forms vias 38 being in contact with the grounding trace 32. Accordingly, the conductive adhesive functions as a grounding face and reduces the parasitic inductance and the parasitic capacitance of the conductive trace pattern. |
