| 摘要 |
PROBLEM TO BE SOLVED: To provide a fluororesin substrate allowing sufficient suppression of warpage occurrence in reflowing and also exhibition of sufficiently excellent, high-frequency properties.SOLUTION: A fluororesin substrate is a fluororesin substrate where a dielectric layer with fluororesin being a main component is formed on a metal conductor and the dielectric layer contains hollow glass beads. The metal conductor has a surface roughness Rz (JIS B 0601-1994) of 2.0 μm or less. The fluororesin is irradiated with ionizing radiation in an irradiation dose of 0.01 to 500 kGy. The fluororesin is one, two, or more kinds of polytetrafluoroethylene (PTFE), a tetrafluoroethylene-perfluoroalkylvinyl ether copolymer (PFA), a tetrafluoroethylene-hexafluoropropylene copolymer (FEP), and a tetrafluoroethylene-ethylene copolymer (ETFE). |
