Challenges and potentials with SiP using FC on LTCC

The current trend towards miniaturization and higher power dissipation offers new challenges for a system in package. This leads to new combinations of materials with different physical properties, processes and designs. (Brunner, 2005) One example of this development is the PAiD-module (power amplifier with integrated duplexer) where a power amplifier is mounted together with a SAW-filter (surface acoustic wave) on a module. The filter characteristic of a SAW-filter is highly temperature depending and therefore the thermal management of the power amplifier must be well controlled. In this paper the impact on thermal performance and reliability of underfill, heat spreader, thermalvias and LTCC (low temperature cofired ceramic) design are discussed