Effects of Active Layer Thickness on the Electrical Characteristics and Stability of High-Mobility Amorphous Indium–Gallium–Tin Oxide Thin-Film Transistors

Herein, we investigated the effects of active layer thickness (tS) on electrical characteristics and stability high-mobility indium–gallium–tin oxide (IGTO) thin-film transistors (TFTs). IGTO TFTs, with tS values 7 nm, 15 25 35 50 were prepared for this analysis. The drain current was only slightly modulated by gate-to-source voltage, in case TFT = nm. Under positive bias stress (PBS), TFTs a less than nm improved as increased. However, negative illumination (NBIS) these deteriorated To explain phenomena, compared O1s spectra thin films different values, acquired using X-ray photoelectron spectroscopy. characterization results revealed that better PBS stability, low NBIS thicker layers mainly due to decrease number hydroxyl groups an increase oxygen vacancies tS, respectively. Among 15-nm thick exhibited best field-effect mobility (µFE) 26.5 cm2/V·s, subthreshold swing (SS) 0.16 V/dec, threshold voltage (VTH) 0.3 V. Moreover, device robust under (?VTH 0.9 V) ?1.87 V).