| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a wiring substrate having superior electric reliability, and a manufacturing method thereof. <P>SOLUTION: The wiring substrate includes a first film layer which has a larger coefficient of thermal expansion in a plane direction along a surface than that in a thickness direction, a resin layer which is formed on the first film layer and has a coefficient of thermal expansion in a plane direction smaller than that of the first film layer in the plane direction, a second film layer which is formed on the resin layer and has a larger coefficient of thermal expansion in a plane direction than that in a thickness direction, and via conductors formed in the first film layer to the second film layer. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
