Compact modeling of the contact effects in organic thin film transistors

The performance of modern organic semiconductor devices is limited by non-ideal effects which are not characterized by traditional models of transport. In this work, we use experimental data from organic thin-film transistors (OTFT) based on Zinc Phthalocyanine that showed a significant influence of contact effects to illustrate how this nonideal effect can be modeled. Using the output current voltage (I_D-V_D) curves of these OTFTs, and different transistor models available in the literature, we illustrate the advantages and disadvantages of each model. We then demonstrate that only a combination of different approaches can accurately describe the experiments in both linear and saturation regions of operation of these OTFTs. The modified procedure has been tested with output characteristics of an ideal transistor with added contact effects with known parameters for the complete transistor.