Research on Failure Detection Method for SiC and GaN Power Devices Based on Frequency Domain Impedance Analysis

The third–generation power semiconductor devices, represented by SiC/GaN materials, undergo long-term operation under complex high-frequency conditions and need to withstand continuous high thermal stress dv/dt, di/dt impacts, which can lead to reliability issues. Common failure types in welded power devices include bond wire fault, solder layers degradation, and Al–pad metallization reconstruction. Moreover, the reliability of the gate oxide layer is an important failure risk for SiC/GaN power devices. In this paper, the correlation between impedance parameters (parasitic inductance, parasitic resistance) and the physical failure of power devices is discovered using Ansys–Q3D frequency domain simulation. By establishing a two–port network measurement system, the power device's frequency domain impedance curves are extracted. Degradation experiments are designed based on typical failure modes, and a mapping model between frequency domain impedance parameters of power devices and physical failures is established using the experimental results. The proposed approach is an effective quality screening technology for high–frequency SiC/GaN power devices without requiring power on treatment.