Mapping the impact of defect distributions in silicon carbide devices using the edge transient-current technique

Abstract

We demonstrate that the multi-photon absorption edge transient-current technique (edge-TCT) can be used to three-dimensionally map the impact of defect distributions on device characteristics in situ inside the bulk of silicon carbide devices. A ∼5 μm wide defect-rich layer induced by proton irradiation at a depth of ∼27 μm was investigated in 4H-SiC samples and compared to the pristine case. Edge-TCT enables mapping of the position of the implantation peak as well as to identify the space charge polarity around the implanted region. The edge-TCT results are compared to Monte Carlo simulations of the proton irradiation that were verified by luminescence measurements and TCAD-based device simulations. In result, edge-TCT is found to be capable of distinguishing different device regions due to its charge sensitivity and directly visualizing space charge regions, facilitating calibration of charge carrier distribution models in semiconductor devices.