Abstract: A multi-layer printed wire board (PWB) structure optimized for improved drop reliability, reliable electrical connections under thermal load, and minimal thickness is provided, along with a mobile terminal, including the PWB. The PWB includes alternating conductive layers and insulative layers. The outermost three layers form an interconnect structure constructed of two conductive layers surrounding an insulative-coated conductive layer. The thicknesses of the various layers are optimized to have an increased resistance to mechanical shock resulting from, for instance, a drop onto a hard surface. In addition, the optimized PWB structure has a minimized thickness and an improved resistance to connection failures resulting from cyclical thermal loads.

Abstract: A multi-layer printed wire board (PWB) structure optimized for improved drop reliability, reliable electrical connections under thermal load, and minimal thickness is provided, along with a mobile terminal, including the PWB. The PWB includes alternating conductive layers and insulative layers. The outermost three layers form an interconnect structure constructed of two conductive layers surrounding an insulative-coated conductive layer. The thicknesses of the various layers are optimized to have an increased resistance to mechanical shock resulting from, for instance, a drop onto a hard surface. In addition, the optimized PWB structure has a minimized thickness and an improved resistance to connection failures resulting from cyclical thermal loads.

Abstract: Surface mount packages having a plurality of polymer and metallic contacts (e.g., balls) applied thereon and methods of fabricating and utilizing such packages are provided. The polymer balls are employed to improve mechanical compliance of the package; and the metallic (e.g., copper) balls are employed to improve thermal conduction between the package and a substrate to which the package is attached. The polymer balls can be located on a periphery portion of a package where mechanical and thermal stresses are the highest; and the metallic balls can be located on a middle portion of the package. Thus the present invention improves both mechanical stresses and thermal conductivity of a second level packaging interconnection, which in turn improves reliability of an electronic device.