Gate Leakage Current of AlGaN/GaN HEMTs Device Influenced by Substrate Defects

The gate leakage currents on the AlGaN/GaN HEMTs on 2-inch SiC epitaxial substrate are measured at Vgs=20 V. The defect image of the wafer observed by the optical surface analyzer and the photograph of fabricated devices on the wafer are superimposed. Comparing the gate leakage current map on the wafer, the relation between the gate leakage current and the location of the defect is found clearl