Thermal reliability of power insulated gate bipolar transistor (IGBT) modules

Thermal behavior of power insulated gate bipolar transistor (IGBT) modules was studied in this paper experimentally. Due primarily to the thermal mismatch in IGBT sandwich structure, thermal stress induced solder fatigue failures, such as the forming and growing of voids and cracks in IGBT solder layers, were quasi-dynamically observed in thermal cycling test. Thermal stress simulation provided stress distribution and bending deformation in IGBT packaging numerically, which is in agreement with the test results. Emitter bonding wire lifting failure and local overheat induced chip burn-out failure, both observed in intermittent operating test, indicate that thermal nonuniform distribution is a main reason affecting IGBT reliability. The study results of this paper are profitable to high reliable IGBT module manufacture and application.