Comparative Analysis of cCGA Solder Column Interconnects Following Aerospace Level Vibration Testing to Failure
Author: Jeffrey Marcus Jennings Company: Harris Corporation Date Published: 9/28/2014
Abstract: In many High Reliability applications, the incorporation of ceramic Column Grid Array (cCGA) packages into circuit card assembly (CCA) designs has become extremely common. The increased utilization for cCGAs stems from their improved reliability in temperature and power cycling when compared with comparable high I/O count package styles like ceramic and plastic Ball Grid Arrays (BGAs). The evidence for this improved performance is documented throughout the literature with numerous studies evaluating the relative reliability for cCGAs versus other package types when exposed to accelerated temperature cycle life testing. These studies have also revealed many of the physics of failure attributes relevant to temperature cycling. Unfortunately when undertaking a similar search for reliability and failure analysis data for cCGAs exposed to extended vibration environments like those commonly experienced in aerospace applications, it is revealed that the available data for this stressing condition is more limited. In addition, many of the available studies were performed on smaller I/O cCGA package styles or for different solder column interconnect configurations that were tested in the current work. In the present study, cCGAs tested to failure at aerospace-type vibration levels are compared with results from the same cCGA devices which are tested to failure in sequential reduced vibration + temperature cycling and temperature cycle only testing. Specifically the two device types evaluated during this study are the Microsemi (Actel) CG624 (1.27 mm pitch) and CG1272 (1.00 mm pitch) with copper wrapped 80/20 Pb/Sn solder column interconnects attached on both ends with eutectic 37 Pb/63 Sn solder. Differences in failure behaviors for the two cCGA package styles under the different environmental testing conditions will be reviewed and discussed.
cCGA, Solder Column Interconnect, Vibration Testing, Life Testing, Failure Analysis