Simultaneous measurements of drain-to-source current and carrier injection properties of top-contact pentacene thin-film transistors

Drain-to-source current [I-DS = (I-D - I-S)/2] and displacement current (1(dis) = I-S + I-D) are evaluated using the simultaneous measurements of source (I-S) and drain (I-D) currents during the application of a constant drain voltage and a triangular-wave gate voltage (V-GS) to top-contact pentacene thin-film transistors. The carrier mobility, threshold voltages and mean potential drops at the source/channel and channel/drain interface are simultaneously obtained from I-DS-V-GS and I-dis-V-GS relationships. Carrier injection properties, namely, the carrier injection voltage at the source electrode and the mean potential drop-V-GS relathionship are discussed on the basis of results of the simultaneous measurements of I-DS and I-dis.