GaAs功率芯片AuSn20共晶焊接技术研究

Study on AuSn20 Eutectic Technology of GaAs Power Chip

针对GaAs功率芯片共晶焊接工艺中,因焊接空洞、虚焊致使芯片烧毁的问题,对AuSn20共晶焊接技术进行研究。通过自动共晶设备,对共晶温度曲线参数进行实验分析。结果表明,共晶温度曲线设置260℃、320℃的温度梯度可以保证焊料的充分融化、浸润,共晶熔融时间控制在15-30s可以形成适量的IMC层。对优化后的共晶焊接面进行热阻分析,在满负荷条件下,功率芯片最高节温为93℃,满足小于125℃的要求,说明共晶质量良好。

In order to solve the problem of chip burnout caused by welding cavity and virtual welding in the eutectic welding process of GaAs power chip,the technology of AuSn20 eutectic welding is studied.The parameters of eutectic temperature curve are experimentally analyzed by automatic eutectic equipment.The results show that the sufficient melting and infiltration of solder can be ensured by setting the temperature gradient of 260℃and 320℃in the eutectic temperature curve,and an appropriate amount of IMC layer can be formed when the eutectic melting time is controlled at 15~30s.The thermal resistance of the optimized eutectic welding surface is analyzed.Under the condition of full load,the maximum temperature saving of the power chip is 93℃,which meets the requirement of less than 125℃,indicating that the eutectic quality is good.