An alternative JEDEC test board design and analysis

摘要

Purpose - The purpose of this paper is to propose an alternative test board design with only one loading condition and sufficiently large sample size, which is more suitable for the statistical package qualification. With the exception of the board shape and size and package component layout, all other aspects of the design strictly follow the JEDEC standard so that the board design can be easily implemented. Design/methodology/approach - A test board in a round shape was introduced. First, drop tests were carried out. Then, the dye stain test and metallurgical analysis were performed in order to study the failure mechanism of lead-free solder joint under drop impact. Findings - The test results indicate that the combined effect of mechanical shock and PCB bending vibration is the root cause of solder joint failure under drop impact, and that the maximum peeling stress of the critical solder joint could be considered to be the dominant failure factor. On the other hand, the fracture of BGA lead-free solder joints occurs at intermetallic compound (IMC) interface near the package side, and failure mode is brittle fracture. Originality/value - These results are the same as those of JEDEC standard test board. Furthermore, the solder joint loading conditions in this design are simplified from six to one. The round test board can take the place of JEDEC standard test board to carry out drop test and to enable good solder joint life prediction and statistical analysis.