Precise parameter extraction technique for organic thin-film transistors operating in the linear regime

We demonstrate a precise parameter extraction for organic thin-film transistors (OTFTs) operating in the linear regime. The precision is achieved by utilizing the mathematical functions YVG and HVG that are derived from measured current-voltage (I–V) characteristics, in a proper sequence. The YVG function compensates for the impact of the contact resistance Rc on the I–V characteristics of the OTFT. The HVG function applied on the YVG function is used to determine the mobility enhancement factor γ > 0, which allows for defining the γYVG function for OTFT that is linearly proportional to the gate-overdrive voltage (VG–VT). The linearity of the γYVG function allows for extraction of the threshold voltage VT and the mobility μ in the OTFT. Using the extracted parameters, the reduction of the experimental data for drain-source resistance with the resistance model for the intrinsic channel allows for accurate determination of RC. The precision of the extraction technique is verified by re-simulation that uses the extracted values of the parameters, and the re-simulation accurately replicates the measurement of the current and the transconductance of the OTFT.