有铅焊膏和无铅BGA混装焊点的可靠性探索

Research on Mixed Joints Reliability of Lead-free BGA and Sn-Pb Solder-paste

目前,无铅器件广泛应用于军用电子产品上,然而很多制造商会将无铅器件进行有铅化处理,这必然会带来其他不可控的因素,最根本的解决办法是通过工艺改进来兼容无铅器件。经过对有铅焊膏焊接无铅BGA的焊接机理进行分析,在设定的回流焊接参数下,使用Sn63Pb37焊膏焊接无铅BGA。混装焊点的X-RAY、金相切片和电镜扫描等质量分析结果显示:混装焊点质量符合要求,在混装焊点和有铅焊点经过500次温度循环试验和振动试验后,二者可靠性相差无几。

Nowadays, the lead-free devices are widely used in the fields of military electronic products. However, many manufacturers transform lead-free devices into lead devices, which will inevitably lead to other uncontrollable factors.The most fun-damental solution is to be compatible with lead-free devices through technological improvements. Through the analysis of the soldering mechanism of lead-free BGA with lead solder paste, the lead-free BGA was soldered with Sn63 Pb37 solder in the setting of reflow soldering parameters. The mixed Joints were qualified through quality analysis of X-ray, metallographic and SEM. The results show that there is not much difference between the reliability of mixed Joints and the SnPb Joints after 500 temperature cycle and vibration test.