Modification of "native" surface donor states in AlGaN/GaN MIS-HEMTs by fluorination: Perspective for defect engineering

We report on AlGaN/GaN MIS-HEMTs with a thermally stable dielectric/AlGaN interface induced by plasma fluorination. The plasma treatment leads to a modification of the "native" surface donors and a fundamentally different device and defect behavior. The feasibility of III-N surface defect modifications shows a new direction for reducing VTh drifts or the possibility of engineering the surface defects.