Temperature effects on the transient measurement of the junction-to-case thermal resistance of IGBTs

The temperature effects on thermal resistance measurement of power modules when applying the transient dual interface measurement method proposed in JESD51-14 is studied in this paper. Simulation and experiment results indicate that the junction temperature should be consistent of two transient cooling curves with and without thermal grease, otherwise the two thermal impedance curves will separate prematurely that result in a lower valuation even an incorrect one of junction-to-case thermal resistance, which is especially obvious for Insulated Gate Bipolar Transistor (IGBT).