Transition-Voltage Method for Estimating Contact Resistance in Organic Thin-Film Transistors

We report a simple method for evaluating the contact resistance (R _C) in organic thin-film transistors, utilizing the measurement of the transition voltage between the linear and saturation regimes in the output characteristics. This method does not need the complex electrode patterning, and thus, it could be useful for the practical R _C test. The R _C extracted from the transition-voltage method shows a decrease with increasing gate voltage, and the results are similar with those extracted from the transfer-line method, indicating the preciseness of the proposed transition-voltage method.