| 摘要 |
PURPOSE:To prevent the deformation and disconnection of conductor patterns for a circuit, and to improve productivity by forming a via hole to a porous layer held between dense layers arranged onto both upper and lower surfaces and shaping the conductor patterns for the circuit connected to the via hole only to the dense layers. CONSTITUTION:A ceramic multilayer substrate 10 includes three layers of dense layers 12, 14 and 16, and a porous layer 18 is disposed held by the dense layers 12 and 14 and a porous layer 20 held by the dense layers 14 and 16 respectively. Conductor patterns 22 for a circuit required are formed onto each one surface or both surfaces of the dense layers 12, 14 and 16. Via holes 24 are shaped at the specified locations of the dense layers 12, 14 and 16 and the porous layers 18 and 20 in order to electrically interconnect the conductor patterns 22 formed to the different dense layers. Accordingly, the generation of the deformation and disconnection of the patterns is prevented, thus improving yield and productivity. |
