压接型IGBT器件内部压力分布

摘要

压接型IGBT器件内部各组件直接堆叠在一起,通过外部压力使得各组件间保持良好的机械与电气接触,进而引入一定比例的接触电阻和接触热阻,所以器件内部的压力分布不仅影响器件内部的电流分布和温度分布,还将严重影响器件的可靠性.基于压接型IGBT器件的有限元计算模型和特殊的应用工况,研究压接型IGBT器件内部的压力分布情况,重点探讨器件内部各组件加工误差与内部的布局方式对器件内部压力分布的影响.通过压力夹具和压力纸等进行压接型IGBT器件内部压力分布的实验,实验结果不仅验证了有限元模型和边界条件的正确性,还表明外部压力加载对器件内部压力分布的影响.%External clamping force is needed to keep all components of press pack IGBTs (PP IGBTs) both electrical and mechanical contact well, which is directly stacked together. It will introduce electrical and thermal contact resistances. Thus, the clamping force is an important parameter for the chip, because it influences electrical contact resistance, thermal contact resistance and power cycling reliability. The clamping force distribution within PP IGBTs is analyzed based on the finite element model and specific application conditions. The impacts of machining tolerance and internal layout of PP IGBTs are discussed. The test bench, including clamping fixture and FUJI prescale, is used to measure the clamping force distribution within PP IGBTs. The experimental results agree well with those using the finite element model. It can not only verify the correct of finite element model and boundary conditions, but also indicate that the external clamping also has a huge influence on the clamping force distribution within PP IGBTs.