Charge carrier mobility in field effect transistors: analysis of capacitance–conductance measurements

We present a formalism to extract carrier mobility and its dependence on charge concentration and electric field, from field effect transistors (FETs) transfer characteristics. In this formalism, we consider the spatial non-uniformity of carrier mobility across the channel. We show that the mobility is extracted accurately by the new method, even when it is strongly dependent on carrier concentration and electric field. Typical examples of carrier mobility extraction in silicon, conjugated polymers, and in AlGaN/GaN heterostructure based FETs are demonstrated.