Intrinsic parameter extraction of a-InGaZnO thin-film transistors by a gated-four-probe method

Abstract

We analyzed the intrinsic electrical characteristics of amorphous InGaZnO (a-IGZO) thin-film transistors (TFTs) using a gated-four-probe method. Based on the back channel potential, the extraction of intrinsic field-effect mobility (μ FEi) and parasitic resistance in source (R s) and drain (R d) electrodes was performed especially for low V GS and V DS conditions. The resulting μ FEi showed typical V GS dependency of amorphous semiconductor TFTs. However, R s and R d showed that there can be non-uniformity in source/drain parasitic resistance, which indicates that a separate analysis of the parameters of each electrode is essential for further improvement of the performance of a-IGZO TFTs. © 2012 American Institute of Physics.