Reliability Analysis of Board Level Assembly with Different Lead Extraction Methods in HTCC Ceramic Packaging

Temperature cycling is one of the important tests for assessing the reliability of packaging products at the board level. Ceramic lead flat packaging shell (CQFP/CSOP) is suitable for surface mount. Due to the mismatch of thermal expansion coefficients between ceramic materials and PCB materials, the device is prone to cracking at the solder joint between the lead and PCB during temperature cycling, leading to failure. The lead plays a role in stress buffering and release between the PCB and the ceramic tube shell. In response to the above situation, this article conducts simulation and experimental verification on the temperature cycling resistance of tube shells with different lead wire lead out forms. Comparing the temperature cycling resistance of different lead out forms of tube shells, a temperature cycling test was conducted on the tube shell, and the failed pins were metallographically sliced. The experiment verified the accuracy of the simulation, and the position of the maximum simulated stress point was the same as the experimental failure position. And calculate the number of temperature cycle lifetimes using the Coffin Manson formula, which is the same as the number of failed temperature cycles in the experiment. By comparing and analyzing the effects of different pin lead out schemes, bending heights, and welding lengths on the temperature cycling resistance of ceramics through simulation. The experimental and simulation results show that the higher the bending height of the lead wire, the higher the number of cycles of temperature fatigue life. When the lead wire adopts a top surface lead out forming structure, the temperature cycle life is much higher than other structures.