| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To solve the problem that, although a conventional composite multilayer substrate is so constituted out of a ceramic substrate and a composite resin material layer formed on the rear surface of the ceramic substrate as to join the ceramic substrate to a printed wiring board via the composite resin material layer, since the respective physical properties (e.g., thermal expansion coefficients) and the respective surface states of the ceramic substrate and the printed wiring board are different from each other largely, it has been difficult to deal with both by a single composite resin material layer, and therefore, there has been the possibility that, when matching the thermal expansion coefficient of the composite resin material layer with the one of either one of the ceramic substrate and the printed wiring board, the interlayer exfoliation and the crack which are caused by thermal impacts occur in the interface on both the sides of which the difference between thermal expansion coefficients is large. <P>SOLUTION: A composite multilayer substrate 1 is the one which so has a ceramic multilayer substrate 2 and so has a resin laminate 3 obtained by laminating first, second, and third resin layers 3A, 3B, 3C as to join the rear surface of the ceramic multilayer substrate 2 to the top surface of the resin laminate 3. Hereupon, the first, second, and third resin layers 3A, 3B, 3C have respectively different thermal expansion coefficients from each other. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
