In this paper we analyze the conduction properties, charge trapping and threshold voltage instability of normally-on β-Ga₂O₃ lateral MOSFETs for high power applications by means of threshold voltage transients. We found that a positive bias applied to the gate induces a rightward shift in the threshold voltage, caused by the trapping of electrons at border traps close to the semiconductor-dielectric interface.

The amount of trapped charge was investigated by an innovative fast-CV experimental setup and was found to follow a logarithmic kinetic in time, modeled by a generalization of the inhibition model that takes into account the effect of columbic repulsion in stress conditions.