| 摘要 |
PURPOSE:To prevent the occurrence of disconnection between a thick-film circuit and thin-film circuit so as to improve the reliability of a multilayered circuit board. CONSTITUTION:The title circuit board is provided with a multilayered ceramic circuit board 1 which-incorporates a thick-film circuit 2 and on the surface of which a via hole 3 filled with a thick-film conductor is led out from the thick-film circuit, stress relieving insulating film 4 formed on the circuit board 1, circuit connecting opening 5 which is formed on the top of the hole 3 in the film 1 and has such a form that its diameter becomes larger as going toward the top, and circuit connecting conductor 6 buried in the opening 5 so that the surface can become nearly flat. In addition, the circuit board has a thin-film circuit 7 which is formed on the film 4 including the hole 5 and is electrically connected to the circuit 2 through the conductor 6 and hole 3. |
