Threshold Voltage Extraction in the Saturation Regime Insensitive to the Contact Properties for Organic Thin-Film Transistors

Abstract

In this work, the conventional threshold voltage ( $V _{\rm th}$ ) extraction method assuming ohmic contacts in organic thin-film transistors (OTFTs) was shown to be difficult to obtain the intrinsic $V _{\rm th}$ values for devices with non-negligible contact properties. A simple $V _{\rm th}$ extraction method based on a modified analytical current–voltage expression in the saturation regime was thus proposed to exclude the influence of the contact properties. By applying the method to experimental devices of two different contacts, apparent $V _{\rm th}$ values close to the intrinsic values were obtained, which proved the method to be useful for accurate device characterization and modeling of OTFTs.