无铅焊料合金压入蠕变性能参数表征研究

微互连焊点高温下的服役可靠性很大程度上决定了电子产品性能的优劣，本文通过微纳米压入法开展了典型无铅焊料合金Sn-3.0Ag-0.5Cu 的高温蠕变性能研究，采用“快速加载–保载–快速卸载”的测试方式获取不同温度下完备的蠕变行为，分析发现温度升高焊料软化加剧、蠕变变形更为明显；得到了焊料合金不同温度下的稳态蠕变应力指数n 与不同硬度下的蠕变激活能Q，分析了温度与硬度对二者的影响并给出激活能Q 与lnH之间的关系．

Creep Parameters Characterization of Lead-Free Solder Alloy Using Micro/Nano-Indentation

Performance of electronic products depends heavily on the service reliability of micro-interconnection solder joints under high temperature. High-temperature creep performance of Sn-3.0Ag-0.5Cu lead-free solder alloy was investigated by micro/nanoindentation, and the testing mode of “rapid loading–holding–rapid unloading” was adopted for obtaining the complete creep behavior of solder alloy under different temperatures. Results show that the solder becomes more softening with increasing temperature, bringing about the more obvious creep deformation. The steady-state creep stress exponent n under different temperatures and the creep activation energy Q under different hardness were obtained. The influences of the temperature and hardness on the two parameters, as well as the relation between the creep activation energy Q and lnH were analyzed.