Composite ceramic board, method of producing the same, optical/electronic-mounted circuit substrate using said board, and mounted board equipped with said circuit substrate

摘要

A composite ceramic board comprising an insulating board of insulating layers of alumina ceramics and dielectric layers of ceramics having a dielectric constant smaller than that of said insulating layers which are fired as a unitary structure, and metallized wirings of a low-resistance conductor such as of Au, Ag, Cu or Pl formed on the surfaces and inside thereof, and a method of producing the same. The composite ceramic board not only has a large strength and a high thermal conductivity but also exhibits excellent high-frequency characteristics and is suited for use as a high-frequency wiring board. The invention further provides an optical/electronic-mounted circuit substrate using the above board, and a mounted board having the circuit substrate of the invention connected to an electronic circuit formed on a mother board.