Failure Analysis of QFP Package Interconnection structure under Random Vibration and Temperature

Nowadays, electronic equipment plays a key and important role in equipment and system, especially with the development of informatization. The failure of interconnect between the chip and PCB, is a major failure mode in electronic equipment, and vibration and temperature are the main environmental factors leading to solder joint failure, which are also the focus of this paper. This study analyzes the failure of QFP chip by random vibration test under three different temperature conditions. The test piece of QFP chip has a self-monitoring circuit, which can monitor its own state whether it is invalid or not. Firstly, the failure of interconnection structure and the effect of their location on reliability has been investigated. Then, the effect of temperature on vibration reliability for interconnection structures has been analyzed. Finally, combined with the exponential distribution of the interconnection structure, the random vibration reliability of the whole chip at different temperatures is evaluated. The results indicate that the interconnection structure of the same chip has similar failure modes, while the crack growth rate is various due to their location, resulting in the difference in their life. Failure modes of interconnect under 25°C and 75°C are similar, which different from failure modes under -25°C, and low temperature reduces vibration reliability of interconnection structure.