Dipole Type Behavior of NO Grown Oxides on 4H–SiC

In this paper, we present surprising MOS capacitor C–V bias instability observed in NO-grown oxides, with distinctly different behavior compared to that of conventional NO-annealed oxides on 4H-SiC. Using sequential back-and-forth and bias-temperature stress C–V measurements, it was demonstrated that the C–V shift direction of NO-grown oxides was opposite to that of NO-annealed oxides. A model based on bias-temperature stress orientated near-interfacial dipoles is proposed to explain this unique behavior of NO-grown oxides.