Component Level Reliability for High Temperature Power Computing with Sac305 and Alternative High Reliability Solders

This experiment considers the reliability of a variety of different electronic components and evaluates them on 0.200” power computing printed circuit boards with OSP. Single-sided assemblies were built separately for the Topside and Bottom-side of the boards. This data is for boards on the FR4-06 substrate. Isothermal storage at high temperature was used to accelerate the aging of the assemblies. Aging Temperatures are 25C, 50C, and 75C. Select data from aging times of 0Months (No Aging, baseline), 6-Months, and 12-Months will be presented. The assemblies were subjected thermal cycles of -40°C to +125°C on a 120 minute thermal profile. The test was subject to JEDEC JESD22-A104-B standard high and low temperature test in a single-zone environmental chamber to assess the solder joint performance. The principal test components are 5 mm, 6mm, 13mm, 15mm, 17mm, 31mm, 35mm and 45 mm ball grid array (BGA) packages with solder ball pitch varying from 0.4 mm to 1.27 mm. Most of the BGA packages are plastic overmolded, while the 31mm and 45mm packages are SuperBGAs (SBGAs). Several surface mount resistors (SMRs) are also considered in order to understand the effect of solder paste composition on paste-only packages. The primary solder for package attachment in this experiment is standard SAC305. Two solders designed for high-temperature reliability are also considered.