IGB模块寿命和可靠性研究.docVIP

IGBT模块的寿命和可靠性研究 系统寿命与可靠性关系：可靠性：产品在一定条件下无故障完成规定功能的能力或可能性   IGBT模块的失效模式： 功率周次 Power cycling： 功率周次用于评估绑定线和Die焊层的机械寿命 Power cycling can estimate the bonding wire and die solder’s lifetime 测试方法: 加载自加热，周期≤ 3秒，测试ΔTvj  Test method: Self heating by load, T_cycle ≤ 3 seconds, measure ΔTvj 失效判据：饱和压降 Vcesat 增大+5%  Failure criteria: Vcesat increase more than 5% 温度周次 Thermal cycling 温度周次用于评估DCB下焊接层的寿命 Thermal cycling can estimate DCB solder’s lifetime 测试方法: 通电加热，周期5分钟，测量ΔTc  Test method: Self heating by load, 5 min/, measure ΔTc 失效判据：热阻Rthjc 增大+20%  Failure criteria: R_thjc increase 20% 失效机理是两种材料不同的膨胀系数 (Different material’s CTE)[ppm/K] 不同应用下IGBT模块的寿命 Lifetime of IGBT module in different application There are many applications and similar types of power modules. Main objective is: how to select an active device in order to reach desired system lifetime? Is it possible to have power module suiting to all applications? 由周期内系统工况变化获得温度变化 Get the temperature profile by power profile in a cycle 温度变化导致的失效模式 Failure modes with ΔT There are two key factors in the selection of the appropriate power module: 1)thermal: Tvj op Tvj max 2)reliability: wear out mechanisms which determine module lifetime as result of module reliability curves and thermal stresses Note: RBSOA and other electrical phenomena are not covered in the presentation. Factors and impacts: 1)TjFWD max ≤ Tvj op TjIGBT max ≤ Tvi op Nowadays Tvj op = 150°C 2)DTjFWD DTjIGBT refer to Power Cycling reliability curves ΔTC refers to Thermal Cycling reliability curves Reliability curves are always given by power module manufacturer 绑定线老化——功率周次曲线 Bond wire degradation – PC curve 功率周次曲线修正因数 PC curve correction factor 基板焊层老化——热循环曲线 Solder on baseplate degradation – TC curve 功率温度循环（PC）次数评估计算 No. of cycle estimation calculation with Power cycling curve 实例：稳态周期系统的寿命估算 Simple mission cycle -- example of lifetime estimation For relative simple mission cycles the module lifetime based on the three presented reliability curves an