Extraction of Sub-Threshold Mobility in Ga2O3 Lateral Transistors From AC Conductance

The sub-threshold mobility in a lateral Ga2O3 transistor is extracted by considering a distributed impedance model of the sub-threshold region. The model explains the occurrence of an observed sharp peak in the AC conductance, which in this case cannot be explained by interface trap states. The trap-free model discussed here reveals two different behaviours of mobility, attributed to scattering regimes where Coulomb scattering is either screened or unscreened. The minimum value of sub-threshold mobility extracted in the unscreened regime corresponds to 0.49 cm2/V-s.