| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a printed wiring board utilized as an interposer and exhibiting stabilized stress reducing action and elastic modulus, even under a sharp temperature change, and to provide a ball grid array package using the printed wiring board. <P>SOLUTION: The printed wiring board 1 is used as an interposer of a ball grid array package, including a three or more multi-layer sheet structure comprising a rigid insulating layer 8 and a porous PTFE sheet 9, wherein the porous PTFE sheet 9 is arranged on an internal layer. <P>COPYRIGHT: (C)2009,JPO&INPIT |
