Temporary wafer bonding materials and processes
Lueck, M., Garrou, P., Malta, D., Huffman, A., Butler, M., & Temple, D. S. (2012). Temporary wafer bonding materials and processes. In International Microelectronics Assembly and Packaging Society (IMAPS) 8th International Conference and Exhibition on Device Packaging, Scottsdale, AZ, March 6-8, 2012,.
Recent years have seen significant advances in temporary wafer bonding with materials providers seeking to meet the growing demands of 2.5D and 3D applications. Many types of temporary bonding solutions have been developed that use different methodologies for bond and de-bond. We have examined four different types of temporary wafer bonding materials for use in two separate applications: a face-up, stackable 3D-IC application with TSVs and backside Cu/Sn interconnects, and a silicon interposer with large TSVs, polymer dielectrics, and solder balls. We present results of the fabrication of these two types of test vehicles and discuss the compatibility of the process flows with the temporary wafer bonding materials. For the 3D-IC application, 15 m thin silicon wafers on three different temporary bond materials were processed through BEOL processes for the passivation, electroplating, and bonding of Cu/Sn microbumps. For the silicon interposer application, results will be reported from a test vehicle lot on the compatibility of two different temporary bond materials with three photoimageable polymer dielectrics and with the process for bumping and de-bonding.