Interpretation of Resistance, Capacitance, Defect Density and Activation Energy Levels in Single-Crystalline MAPbI3

Hybrid inorganic-organic lead halide perovskites have attracted a significant research interest in last 10 years due to its broad area applications in optoelectronic devices such as solar cells, lasers, photodetectors and LEDs. Fundamental understanding of the charge transportation, defect density and activation energy is very important for the further progress of this class of semiconductor. Here, we shed light on the interpretation of resistance, capacitance, defect density and activation energy levels in single-crystalline MAPbI3. In particular, impedance response of MAPbI3 crystal as a function of applied bias and temperature (under both increasing and decreasing temperature cycles) is studied for the first time. From the detailed bias and temperature studies, we found that the low frequency capacitance values are influenced by ion density and mobility. Consequently, single-crystalline MAPbI3 depicts an activation energy of 0.46-0.47 eV with an exceptionally low electronic trap density of 0.96×10^10 c...