The effects of the microstructure of ZnO films on the electrical performance of their thin film transistors

Abstract

This study examined a fundamental aspect of ZnO-based thin film transistors (TFTs): the connection between the deposition conditions and the microstructure of ZnO films, and the electrical performance of the TFTs. We characterized the microstructure of ZnO films deposited under various rf powers by using high resolution transmission electron microscopy and x-ray diffraction. In further investigating the effects of the microstructure on the device performance, we experimentally demonstrated that the electrical mobility of the devices was coupled to the grain size of the ZnO films in an exponential function.