Impact of crystalline defects in 4H-SiC epitaxial layers on the electrical characteristics and blocking capability of SiC power devices

In this study, we report the impact of structural 4H-SiC epitaxial defects on the electrical characteristics and blocking capabilities of SiC power devices. The detection and classification of the various crystal defects existing in 4H-SiC epitaxial layers and substrates was carried out with a commercial inspection tool using an optical microscope with a photoluminescence channel (PL). After the fabrication of dedicated test structures, devices that contain a single crystal defect were selected and electrically tested in reverse bias mode. Photon emission microscopy was performed to enable the localization of the leakage current spots within the devices. Thus, a direct correlation of the various crystal defects with the reduced blocking capability mechanism was made. This evaluation helps to set directions and build a strategy towards the reduction of critical defects in order to improve the performance of SiC devices for high power applications.

Automated summary

In this study, the impact of structural 4H-SiC epitaxial defects on the electrical characteristics and blocking capabilities of SiC power devices was investigated. The correlation between crystal defects and reduced blocking capability mechanism was determined, providing insights for improving the performance of SiC devices for high power applications.