| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To solve the problem that defective electrical connection is caused by thermal stress between an electronic element and insulating layers due to a large thermal expansion differential between the element and the insulating layers. <P>SOLUTION: A multilayered wiring board 9 with a built-in electronic element is constituted by laminating a plurality of insulating layers 3 composed of organic materials upon another and, at the same time, forming wiring conductors 4 on the surfaces of the insulating layers 3. In addition, the wiring conductors 4 positioned on the upsides and undersides of the insulating layers 3 are connected to each other through via conductors 5 formed in the insulating layers 3, and the electronic element 8 having lead-out electrodes 10 electrically connected to the wiring conductors 4 or via conductors 5 are contained in a cavity 7 provided in at least one of the insulating layers 3. At least the insulating layers 3 positioned immediately above and below the electronic element 8 have coating layers 2 formed by coupling inorganic insulating powder with a thermosetting resin on the upper and lower surfaces of liquid crystal polymer layers 1. Each coating layer 2 is formed so that the content of the inorganic insulating powder may decrease as going toward the opposite side from the polymer layer 1 side. <P>COPYRIGHT: (C)2004,JPO&NCIPI</p> |
