[16p-E102-1~12] 21.1 Joint Session K "Wide bandgap oxide semiconductor materials and devices"

▲ [16p-E102-8] Transient Photocapacitance Spectroscopy of Deep-levels in (001) β-Ga₂O₃

〇(DC)Fenfen Fenda Florena¹, Aboulaye Traore¹, Takeaki Sakurai¹ (1.Univ. of Tsukuba)

Keywords:semiconductors, defects, physical properties

Defect levels in (001) β-Ga₂O₃ were investigated using transient photocapacitance (TPC) spectroscopy. For sub-band photon energies in the range of 1.13−3.10 eV, the TPC signal showed broad optical absorption at room temperature. Using the theoretical Pässler model, deep-level states at E_T = 1.15 eV (Trap 1) and E_T = 1.79 eV (Trap 2) were demonstrated. The Franck-Condon energies (D_FC) of Traps 1 and 2 are 0.11 eV and 0.66 eV, respectively. The TPC measurements have been performed at temperatures ranging from 30 to 360 K. From 150 to 360 K, the TPC signal of Trap 1 decreased as the temperature increased. The decrease in the TPC signal of Trap 1 agreed with the thermal quenching model, and a thermal activation energy of 156 meV was estimated. Moreover, the effective phonon energy of β-Ga₂O₃ have been extracted. From 30 to 360 K, the effective phonon energy was in the range of 80 − 126 meV.