層間バンプ接続法(B^2it^<TM>)配線板の熱特性評価 Thermal Management Estimations for B^2it^<TM>)Printed Wiring Boards with Bump(Filled Via Hole)Interconnection
We have developed B<SUP>2</SUP>it<SUP>TM</SUP> (Buried Bump interconnection technology) printed wiring boards (PWB's) for high density and high performance wiring boards or substrates. Ordinary PWB's have low thermal conductivity because of their organic materials, compared with ceramic substrates and so on. The B<SUP>2</SUP>it<SUP>TM</SUP> PWB's have filled via holes by silver paste bumps to connect wiring lines between neighbor layers. The feature is different from ordinary PWB's having copper-plated through holes. This paper reports the thermal management properties for the B<SUP>2</SUP>it<SUP>TM</SUP> PWB's by measuring the thermal resistance of several filled via hole situation. And a thermal conductivity of the via hole material was simulated from the measurement values. As the results, the thermal conductivity of the via hole was very high to compare with that of the normal printed silver paste, and the B<SUP>2</SUP>it<SUP>TM</SUP> PWB's had good thermal management property enough to high density packaging.
回路実装学会誌 13(1), 44-49, 1998-01-20
The Japan Institute of Electronics Packaging