| 摘要 |
Ceramics for wiring boards having an SiO2 crystal phase, a spinel type oxide crystal phase containing Mg or Zn and Al and a composite oxide type crystal phase containing at least Sr, Al and Si, and having a coefficient of thermal expansion of not smaller than 5.5 ppm/° C. at room temperature through up to 400° C., a dielectric constant of not larger than 7, and a dielectric loss of not larger than 50x10-4 at 20 to 30 GHz. The ceramics can be obtained by the co-firing with a low-resistance metal such as copper or silver, and can be advantageously applied for the production of a wiring board for treating, particularly, signals of high frequencies. Furthermore, the ceramics has a coefficient of thermal expansion which is so large as can be brought close to the coefficient of thermal expansion of the semiconductor element such as GaAs or of the printed board. Therefore, the wiring board produced by using the ceramics makes it possible to effectively prevent the mounting portions from being damaged by the difference in the thermal expansion.
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