Reliability of high Tg copper clad laminate for lead-free assembly

A general property review of high Tg copper clad laminate materials is reported. The characteristics of both dicy-cured and PN-cured materials are discussed. The properties of PN-cured materials are compared with those of conventional dicy-cured high Tg materials. These PN-cured materials have shown enhanced thermal resistance. In addition, a low thermal expansion high Tg material is also presented. The advantages of lowering thermal expansion of a material are reported based on several experimental results. The properties of laminates studied include Tg, thermal decomposition temperature, thermal expansion, and time-to-delamination, drilling processability, and interconnect stress test. The results of the tested materials are presented and the recommendation for material selection is also discussed.