Practical Challenges of High-Power IGBT’s I-V Curve Measurement and Its Importance in Reliability Analysis

This paper examines the practical challenges of simplified setups aimed at achieving high-power IGBTs’ IC–VCE curve. The slope this I–V curve (which is defined as on-resistance RCE) and point where VCE–VGE visibly bends (threshold gate voltage) can be suitable failure precursor parameters to determine an IGBT’s health condition. A simplified/affordable design for these specific measurements used in-situ condition monitoring or field testing switching devices. First, possible measurement methods are discussed in detail order prevent self-heating. selected includes two IGBTs which high-side IGBT was device under test (DUT) with a constant voltage (VGE) 15 V. Then, low-side switched by short pulse (50 μs) impose high-current on DUT. also extracted important failure-precursor indicator. In next stage, power-cycling performed, impact degradation analyzed methods. results show that after 18,000 thermal cycles, visible shift seen. internal resistance increased 13%, while initial collector-emitter knee slightly changed. It likely our case, during performed aging process, bond wires were most affected, but hypothesis needs further investigation.