“…Fortunately, using high-dielectric-constant (high-) materials to replace SiO2 as gate layer can simultaneously enable a low leakage current and a low-voltage operation. Various high-materials, e.g., Y2O3 4 , Al2O3, 9,10 HfO2, 2,11 Ta2O5, 12 HoTiO3, 13 HfLaO, 14,15 LaLuO3, 16 LaAlO3, 17 have been reported for a-IGZO TFTs. However, for high-materials, there is a general phenomenon that the band gap decreases with the increase of the value.…”