Robust C–V Ratio Technique for Profiling Defects in Proton‐Irradiated 4H‐SiC

ABSTRACT Silicon carbide (SiC) power devices possess exceptional electrical and thermal properties, making them strong candidates for deployment in extreme environments such as space. However, displacement damage induced by high‐energy particles remains a critical factor that can compromise long‐term reliability, underscoring the need for accurate defect characterization. Conventional C–V doping‐profile extraction uses numerical differentiation, which amplifies measurement noise and reduces accuracy and reproducibility. We present an analytical model that removes numerical differentiation by using the ratio of C–V characteristics measured before and after irradiation. This approach enables direct, stable, quantitative extraction of net radiation‐induced trap density. To validate the method, we irradiate 4H‐SiC Schottky barrier diodes with 55 MeV protons at a fluence of 1 × 10 14 cm −2 and compare the extracted trap densities with those from the conventional differentiation‐based technique to assess consistency and robustness. Furthermore, based on the extracted trap‐density profiles, we introduce a formula for determining an effective trap energy level parameter, which serves as a diagnostic indicator for identifying the dominant displacement‐damage mechanisms under high‐energy proton irradiation. The proposed analytical model operates at room temperature, requires standard C–V measurements, and serves as a fast, accurate tool for screening displacement damage effects in SiC power devices.