结温对双界面法测量功率模组R_(thJC)的影响

The Junction Temperature Influence on the Dual Interface Method for the Power Module R_(thJC) Measurement

JEDEC 51-14标准的瞬态双界面法(TDIM)是指让半导体器件通过相等的加热电流,分别测量器件散热面通过两种不同导热介质与散热器相接触时的瞬态热阻抗曲线,利用两条瞬态热阻抗曲线的分离点来确定待测器件的结-壳热阻R。但在相等的加热电流测试条件下,有的功率器件会出现热阻抗曲线提前分离的现象。此处首先列举了绝缘栅双极型晶体管(IGBT)功率模组在不同结温下的测试数据,定性地介绍该现象。其次,从材料热力学的角度对该现象的物理机制进行了理论分析。最后,基于自研IGBT功率模组进行定量计算及实测验证,对比结果表明所提热力学改进模型与实测结果吻合。

The transient dual interface method(TDIM) of the JEDEC 51-14 standard means that when the semiconductor device passes the same heating current,the transient thermal impedance curves of the heat dissipation surface of the device in contact with the radiator through two different heat conduction media are measured,and the separation point of the two transient thermal impedance curves is used for determining the junction-to-case thermal resistance Rof the device under test.However,under the same heating current test conditions,premature separation of the thermal impedance curves of some power devices is found.Firstly,the phenomenon is analyzed and summarized by presenting the test data of insulated gate bipolar transistor(IGBT) power module measured at different junction temperatures.Secondly,the physical mechanism of this phenomenon is analyzed theoretically from the perspective of material thermodynamics.Finally,the quantitative calculation and experimental verification based on the self-designed IGBT power module are carried out,the comparison results show that the proposed thermodynamic improved model is in good agreement with the measured results.