Low temperature dielectric material for embedded micro wafer level packaging
In this paper, we have developed the evaluation results of low cure temperature (less than 200 deg C) dielectric materials in terms of process ability and adhesion on SiN and mold compound substrates. The results showed that the low cure temperature dielectric materials have good adhesion on SiN and mold compound substrate. Integration of thin film passives like inductors, capacitors and band pass filters are also demonstrated on this mold compound wafer platform using electroplated Cu and low cure temperature dielectric material. Developed thin film passives on mold compound wafer platform have significantly improved the passives performances that are benchmarked against high resistivity silicon wafer (HiRSi). Reliability test vehicles are fabricated using Cu RDL, low cure temperature dielectric material and electroplated Cu UBM with SAC solder bump interconnects. A complete description of dielectric material evaluation for EMWLP, process development of thin film passive fabrication and multi-layer RDL integration on reconstructed mold compound wafer has been discussed.