Density-of-States Modeling of Solution-Processed InGaZnO Thin-Film Transistors

The effects of Ga composition on the performance of InGaZnO (IGZO) thin-film transistors (TFTs) prepared by a sol-gel method are investigated, and the density of states (DOS) is characterized by the device modeling. The TFT mode is changed from a depletion type to an enhancement type, and the extracted DOS parameters are reduced with the increase of Ga contents. The extracted DOS distribution has a higher peak value than that of an IGZO TFT prepared by physical vapor deposition.