Improvement in the Performance of Sol–Gel Processed In 2 O 3 Thin-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.