[6a-A203-1~10] 21.1 Joint Session K "Wide bandgap oxide semiconductor materials and devices"

△ [6a-A203-1] Deconvolution of near-valence band maximum states in amorphous oxide semiconductor

〇Keisuke Ide¹, Yosuke Kishida¹, Takayoshi Katase¹, Hidenori Hiramatsu^1,2, Shigenori Ueda³, Hideya Kumomi², Hideo Hosono^1,2, Toshio Kamiya^1,2 (1.MSL, Tokyo Tech., 2.MCES, Tokyo Tech., 3.NIMS)

Keywords:amorphous oxide semiconductor, defect, photo electron microscopy

Amorphous oxide semiconductor shows response to the visible light even though the bandgap is ~3.0 eV. This is attributed to large amount of defect states just above valence band maximum. However, the origin of this state have not been clear. In this study, we used difference-method from photo-electron spectrum to distinguish and extract several origin, such as void, hydrogen, and vacancy.