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摘要

"The Influence of Die Size on the Thermal Fatigue Reliability of a Chip Array BGA"A thermal cycling test program was developed to evaluate the effect of die size and distance from neutral point (DNP) on the thermal fatigue reliability chip array ball grid array (CABGA) fabricated and assembled with SAC 305 solder balls and paste. A daisy-chained 192 I/O CABGA package with a 14×14mm body size was fabricated with square die of 12mm, 9.5mm or 7.2mm to produce diagonal die-to-package ratios of 0.86, 0.68, and 0.51 respectively. The finished components were surface mount-assembled onto 0.93"-thick daisy-chained test boards. Accelerated thermal cycling was performed in single-zone, air-to-air chambers using cycling profiles of 0°/100℃ (IPC-9701 TC1) and -40°/125℃(IPC-9701 TC3). Event detection was used for in situ resistance monitoring and failure detection. The results of the thermal cycling tests are discussed in terms of the influence of die size and DNP on time-to-failure, the failure location in the package, and failure mode. (SMTA International, September 2016)