Frequency Response Characteristics Depending on the Metal Capping Structure and Length of the Amorphous SiZnSnO Thin Film Transistor

Abstract

Amorphous oxide semiconductors (AOSs) have already been adopted as a channel layer in the display industry and have recently expanded their scope. A study to improve the properties of these AOSs is being conducted extensively. The electrical characteristics are improved by applying a metal capping (MC) layer structure to amorphous Si-Zn-Sn-O (a-SZTO). The characteristics of the MC layer structure systematically improved according to its length. The high mobility of 76.69 cm(2)/Vs is shown in the MC layer with 40 mu m length. It was confirmed that the MC layer structure operates stably even at a current level that is one order higher (approximate to 10(-3) A) than the conventional structure (approximate to 10(-4) A) in the gate pulse switching characteristics. Mainly because the MC layer structure is less affected by the injected electrons and the interface trap density between the channel and the gate insulator. If the MC layer is applied, it is expected to operate in a high-frequency region while maintaining a high current level.