Development of the embedded LSI technology in PALAP/spl trade/

We are developing the embedded LSI technology in PALAP/spl trade/; PWB developed by DENSO CORP.; made from plural patterned thermoplastic resin films and fabricated with one time hot press process. To understand the behavior of the resin, via, copper land, LSI and so on during press process, a new strong coupling analysis system was developed. Using this system, we analyzed the velocity of resin around the LSI, when embedding the LSI. As a result, it was cleared that the resin under the LSI flowed toward the clearance, and the velocity sharply increased at peripheral position of the LSI. Practically, via under the LSI radially moved from the LSI central part according to the velocity distribution. It is not concerned with the positional relationship between the LSI bump and via that the clearance is different from each other at the left right of the LSI, because the LSI moves with the resin at the same timing and velocity.