EFFECT OF THE DISTRIBUTION OF STATES IN AMORPHOUS IN-GA-ZN-O LAYERS ON THE CONDUCTION MECHANISM OF THIN FILM TRANSISTORS ON ITS BASE

Amorphous In-Ga-Zn-O Thin Film Transistors (a-IGZO TFTs) have proven to be an excellent approach for flat panel display drivers using organic light emitting diodes, due to their high mobility and stability compared to other types of TFTs. These characteristics are related to the specifics of the metal-oxygen-metal bonds, which give raise to spatially distributed s orbitals that can overlap between them. The magnitude of the overlap between s orbitals seems to be little sensitive to the presence of the distorted bonds, allowing high values of mobility, even in devices fabricated at room temperature. In this paper, we show the effect of the distribution of states in the a-IGZO layer on the main conduction mechanism of the a-IGZO TFTs, analyzing the behavior with temperature of the drain current.