Improvement in the Performance of Sol–Gel Processed In2O3Thin-Film Transistor Depending on Sb Dopant Concentration

Solution-processed Sb-doped In ₂ O ₃ thin-film transistors (TFTs) have been fabricated. To improve the electrical performance, In ₂ O ₃ was doped with Sb, which exhibits a higher standard electrical potential than In and acts as a booster to create more oxygen vacancies and extra electrons. We observed that as the doping concentration increases, the oxygen deficiency of In ₂ O ₃ and the concentration of Sb ⁵⁺ increases, leading to an increase in the field-effect mobility. Doping with an appropriate amount of Sb resulted in a significant improvement of the field-effect mobility of TFTs. A TFT exhibiting a high mobility of 1.6 cm ² /Vs and an ON/OFF current ratio of 10 ⁴ was obtained. A field-effect mobility of ten times higher than that of single In ₂ O ₃ TFTs was achieved.