| In this thesis, ZnO-TFT is fabricated by magnetron sputtering and sol-gel technology respectively. In order to improve the electronic properties of ZnO-TFT, as-prepared ZnO thin film is annealed at different temperature and the thickness of ZnO thin film is changed.Firstly, ZnO thin film is grown on cleaned Si/SiO2 substrate directly by sputtering method, then annealed at 300℃,400℃and 500℃respectively. It is shown from XRD and AFM results that the crystallization of ZnO thin film is improved along with the increasing of annealing temperature. Then three kinds of ZnO-TFT are fabricated based on annealed ZnO thin film at different temperature. The field effect mobility of different TFT increases from 0.8×10-2 cm2/Vs to 5.0×10-2 cm2/Vs, Ion/Ioff ratio increases from 3×102 to 2.8×103, and Vth decreases from 34V to 26V when the annealing temperature of ZnO increases from 300℃to 500℃.Secondly, ZnO-TFT with different ZnO thickness 48nm,60nmand 72nm are prepared respectively. Before preparing TFT, All ZnO film are annealed at 500℃and show a good crystallization by SEM measurement. The field effect mobility of different TFT increases from 6.9×10-2cm2/Vs to 2.12×10-1cm2/Vs, and Vth decreases when ZnO thickness decreases from 72nm to 48nm. Ion/Ioff ratio is about 4.2×102 for all devices.Finally, we prepared ZnO thin film at Si/SiO2 substrate by sol-gel method. Then as-prepared ZnO films are annealed at 300℃or 500℃respectively. It is shown that the crystallization of ZnO film annealed at 500℃is better than that of ZnO film annealed at 300℃. Two kinds of ZnO-TFT are fabricated based on two annealed ZnO films. The mobility of ZnO-TFTs annealed at 300℃and 500℃are 1.28×10-3cm2/Vs and 2.42X 10-2cm/Vs, Vth are 21V and 5V, respectively. Ion/Ioff ratio is about 4.0×102 for two kinds of TFTs. In addition the electronic properties of ZnO-TFT prepared by sol-gel method is bad than that of ZnO-TFT prepared by sputtering at moment, but sol-gel technology has a potential for low-cost, large area production.
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