| abstract |
A wiring board has a base insulating film. The base insulating film has a thickness of 20 to 100 μm and is made of a heat-resistant resin which has a glass-transition temperature of 150° C. or higher and which contains reinforcing fibers made of glass or aramid. The base insulating film has the following physical properties (1) to (6) when an elastic modulus at a temperature of T° C. is given as D T (GPa) and a breaking strength at a temperature of T° C. is given as H T (MPa).n (1) A coefficient of thermal expansion in the direction of thickness thereof is 90 ppm/K or less (2) D 23 ≧5 (3) D 150 ≧2.5 (4) (D −65 /D 150 )≦3.0 (5) H 23 ≧140 (6) (H −65 /H 150 )≦2.3. |