ZnO-Based Thin Film Transistor Fabricated Using Radio Frequency Magnetron Sputtering at Low Temperature

Abstract

Thin film transistors (TFTs) were fabricated on a glass substrate using zinc oxide material as a channel layer. The layers were grown by radio frequency magnetron sputtering method at a temperature of 100°C. The output characteristics of a TFT device showed that there is a reduction in drain current at increased drain-source voltage and gate-source voltage. This evidenced the existence of self-heating effect which may be due to increased donor type point defects. The electrical characteristics of a device show an improved intrinsic channel mobility of 4 cm2/Vs, threshold voltage of 12 V, sub-threshold swing of 1 V/decade, and very much decreased off current of the order 10−12 A.