Sol-Gel Derived Dip Coated ZnO – La₂O₃Thin Film Transistors

Abstract

ZnO thin films are fabricated utilizing a cost effective sol-gel dip coating technique and potentially applied as active material in thin film transistors (TFT). The channel length of the TFT is maintained at 40 μm. Thermally deposited high -k La 2 O 3 is used as dielectric material. The fabricated ZnO films are annealed in oxygen atmosphere at 500 • C for 1 hour and characterized by XRD, EDX and SEM analysis. The TFTs are fabricated in top gate coplanar electrodes structure on glass substrates. The electrical characteristics of the TFTs are investigated and some important electrical parameters are evaluated. The TFTs exhibit field effect mobility of 1.9 cm 2 /VS, low threshold voltage of 2.5 Volt, high ON/OFF current ratio of 10 7 , sub-threshold swing of 0.8V/decade, transconductace of 1.2 × 10 −3 mho and gain band-width product of 20 kHz.