[8p-Z26-1~23] 16.1 Fundamental properties, evaluation, process and devices in disordered materials

[8p-Z26-4] Defect states in amorphous selenium films

〇Tamihiro Gotoh¹, Shogo Kuroiwa¹ (1.Gunma Univ.)

Keywords:selenium, defect states, photothermal deflection spectroscopy

Amorphous selenium (Se) is a semiconductor material with excellent photoelectric properties, and its application to high-sensitivity image tubes and X-ray image sensors is progressing. These utilize the high electric field phenomenon, and the defect level in the band gap plays an important role. Details of the defect level of amorphous Se are becoming clear from experimental and theoretical considerations. Photothermal deflection spectroscopy (PDS) is a method that enables highly sensitive observation of defect levels in semiconductor thin films. The subgap optical absorption of amorphous Se is evaluated by analysis including the signal of the substrate superimposed on the PDS spectrum, and the details of the defect level are clarified.