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Amorphous metal oxides semiconductors,particularly InGaZnO(IGZO),have attracted great attention due to their superior properties,such as high electron mobility(> 10 em2/Vs),excellent optical transparency in visible light region,and large-area uniformity by conventional sputtering methods even at room temperature.To date,most research on IGZO-based devices has focused on thin-film transistors,but effort on p-n and Sehottky diodes is yet much limited.So far,the limited studies on IGZO-based Schottky diodes generally focused on the device performance and the influences of thermal and interface treatment,and anode or cathode metals,for diodes with particular IGZO-thicknesses(e.g.only one or two thicknesses)[1-3].We have systematically investigated the influences of processing conditions to the performance of Schottky diodes with a structure of Pd/a-IGZO/Ti/Au [4].All diodes are fabricated on glass but at room temperature without any thermal treatment,so that the results are relevant to possible applications on flexible plastic substrate.During the RF magnetron sputtering process of the IGZO layers,various RF powers(50~130 W),oxygen content(0~15%),and IGZO-thicknesses(25~200 rim)were applied to optimize the process parameters.The results indicate that high performance Schottky diodes with high rectification ratio(e.g.~106),high barrier height(~0.8 eV),low ideality factor(minimum 1.07)can be realized by using a-IGZO layers sputtered at relatively low RF powers(≤ 70 W)and oxygen content of~2.5-5%.The breakdown voltage shows no clear dependence on the RF powers and oxygen contents but a near linear dependence on the a-IGZO thickness.High breakdown voltage~-15 V can be obtained for the diode with 200-nm-IGZO.