| 摘要 |
PURPOSE:To secure the mechanical strength of a multilayered ceramic circuit board while the dielectric constant of the substrate is lowered by making the matrix in, the peripheral area of wiring porous and the matrix in the other area compact. CONSTITUTION:A lamination element A is formed by printing a gland layer 3 on a green sheet 2 having a smaller ceramic grain size and another lamination element B is formed by printing wiring 1 on another green sheet 2. Then a lamination element C is formed by printing the gland layer 3 on a green sheet having a larger ceramic grain size. Each set is constituted of the three kinds of lamination elements A, B, and C by piling up the element A, element B, element B, and element C in this order and, after a plurality of sets are piled up, the green sheet 4 is put on the top. Such laminated body is sintered after press molding and the matrix of the peripheral area of the wiring 1 is formed to a porous area 2' and the matrix of the other area is formed to a compact area 4'. |
