LAUSR

We analyzed the I-V hysteresis behaviors of tin perovskite (MASnI3, MA: CH3NH3) thin films using impedance spectroscopy coupled with charge modulation spectroscopy (CMS). The capacitance-voltage (C-V) characteristics of the ITO/MASnI3/Al device showed hysteresis behaviors, in accordance with the trap filling process suggested by the I-V characteristics. The CMS measurement indicated the enlargement of the energy bandgap of the MASnI3. On the basis of these results, we proposed a model that trap states in the vicinity of the bottom of conduction band are filled, and concluded that the trap filling process occurring at Sn vacancies makes a significant contribution to the electrical properties of tin perovskite film and the hysteresis of the I-V and C-V characteristics of our device. The I-V hysteresis is suppressed with the decrease of defects such as Sn vacancies in MASnI3 films.We analyzed the I-V hysteresis behaviors of tin perovskite (MASnI3, MA: CH3NH3) thin films using impedance spectroscopy coupled with charge modulation spectroscopy (CMS). The capacitance-voltage (C-V) characteristics of the ITO/MASnI3/Al device showed hysteresis behaviors, in accordance with the trap filling process suggested by the I-V characteristics. The CMS measurement indicated the enlargement of the energy bandgap of the MASnI3. On the basis of these results, we proposed a model that trap states in the vicinity of the bottom of conduction band are filled, and concluded that the trap filling process occurring at Sn vacancies makes a significant contribution to the electrical properties of tin perovskite film and the hysteresis of the I-V and C-V characteristics of our device. The I-V hysteresis is suppressed with the decrease of defects such as Sn vacancies in MASnI3 films.