Figure 7: Determining the mobility.
From: Mobility overestimation due to gated contacts in organic field-effect transistors

(a) The capacitance in the channel (c′A, where A is the area of the transistor). (b) Mobility for the reverse (negative to positive VGS) sweep: the differential mobility (solid line) calculated from the linear transistor characteristics using equation (1) and mobility (dashed line) calculated from equation (8) using the channel properties obtained from the fit to impedance data.