| 摘要 |
PROBLEM TO BE SOLVED: To prevent the occurrence of deformation, such as irregularities, strain, etc., and cracks in an insulating layer composed of a fluorine resin having a low dielectric constant when the insulating layer is heat-treated at a high temperature. SOLUTION: A wiring board having a low dielectric constant and a superior high-frequency characteristic is obtained by providing an insulating layer 3 formed by mixing a fluorine resin and a siloxane resin at a weight ratio of 6:4 to 4:6 in the wiring board. Consequently, the glass transition temperature Tg and softening temperature of the insulating layer 3 are made higher than those of the fluorine resin, and the elongation of the layer 3 by softening is suppressed to a small value. When the insulating layer 3 is formed in the above- mentioned way, the occurrence of deformation, such as irregularities, strain, etc., or cracks in the layer 3 is prevented even when the layer 3 is heat-treated at a high temperature. |
