| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a coil built-in substrate in which a forming layer of a coil conductor 9 is arranged at a location displaced from half the height and deterioration in electric characteristics of the coil conductor as an inductor is inhibited. <P>SOLUTION: A coil built-in substrate 101 comprises a first magnetic material layer 21 in which a coil conductor 9 and a magnetic material are laminated, a first surface layer 31 formed on an electronic component mounted surface side (first principal surface side) and including a surface conductor film 7, and a second surface layer 32 formed on a mounting surface side (second principal surface side) with respect to a wiring board that is a mounting destination and including the surface conductor film 7. A second magnetic material layer 22 is provided between a coil conductor formation layer 21c that is a layer including the coil conductor 9, and the first surface layer 31. Assuming that a distance between the coil conductor formation layer 21c and the first surface layer 31 is represented as A, a distance between the coil conductor formation layer 21c and the second surface layer 32 as B, magnetic permeability of the first magnetic material layer 21 as μ1 and magnetic permeability of the second magnetic material layer 22 as μ2, there are relationships of A<B, μ1<μ2. <P>COPYRIGHT: (C)2012,JPO&INPIT |
