Results presented in this letter demonstrate that the effective channel mobility of lateral, inversion-mode 4H-SiC MOS-FETs is increased significantly after passivation of SiC/SiO2 interface states near the conduction band edge by high temperature anneals in nitric oxide. Hi-lo capacitance-voltage (C-V) and ac conductance measurements indicate that, at 0.1 eV below the conduction band edge, the interface trap density decreases from approximately 2 × 1013 to 2 × 1012 eV-1 cm-2 following anneals in nitric oxide at 1175 °C for 2 h. The effective channel mobility for MOSFETs fabricated with either wet or dry oxides increases by an order of magnitude to approximately 30-35 cm2/ V-s following the passivation anneals.
- Interface states
- Silicon carbide
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering