Low-CTE Materials for Printed Wiring Boards

摘要

The results of this investigation proof, that reducing the CTE of base-materials for PWBs is a very effective way to increase the reliability of PCBs. Depending on the application it may be enough to reduce the CTE in plane of the board for a better reliability of the interconnection between the PWB and surface-mounted devices. This can be done by using standard-material for the major part of the multilayer and material with alternative reinforcements for the outer layers. Even better reliability can be reached by building the whole mulitlayer with material, that has Iow-CTE-properties in all 3 dimensions. Current developments in telecommunication, automotive and other markets will raise a demand for PCBs with higher component density and reliability. Therefore low-CTE-application will gain importance. The development of new materials and the further development of new concepts of PWB-build-ups will be the answer of the suppliers to this challenges. This process has already been started and several products are available, but there still is a lot of work to be done.