Third quarterly report for TRP Flip Chip Attach

This report contains two separate reports for the Flip Chip Attach project. The first report is Yorktown`s report as per their deliverable 1.6 on the rheological properties of the material. Since the paste dispensing process is preformed at shear rates above 100/s and in the low Reynolds`s number, i.e., creeping flow regime, the authors have designed viscometry measurements to simulate the response under these conditions. The study determines simple parameters and criteria to obtain paste properties that may achieve high resolution dispensing. They compare and contrast their material with ``the best in the business``. They set forth a criteria for optimum screenability and demonstrate the high resolution dispensability of Yorktown pastes. Three Yorktown and two of the best commercial pastes are reported in this study. The second report documents a designed screening experiment to identify significant bonding variables. The bonding experiments were performed with the electrically conductive adhesive paste developed by Ravi, Saraf, and Sambucetti of the IBM Research Center at Yorktown Heights, NY. Eight bonding variables were incorporated in a two level factorial design with 16 trials. Palladium-nickel alloy plated copper coupons were used to simulate chips and substrates for this investigation. The shear tested chips were examined for fracture appearance characteristics. Only 11 of 46 chips displayed 50% or greater cohesive fracture. The most significant variables have been identified as bond pressure, temperature, and dwell time