Extraction of interface trap density by analyzing organohalide perovskite and metal contacts using device simulation

Abstract

We estimated the interface trap density by examining methylamine-lead-iodide (MALI, CH3NH3PbI3) and metal contacts. We analyzed experimental current-voltage curves from two MALI-based resistive memory devices, which are Au/MALI/indium-tin-oxide and Ag/MALI/Pt, using a device simulator. We obtained effective work functions (EWFs) for MALI/metal contacts by considering Fermi level pinning attributed to the interface states comprising metal-induced gap states (MIGSs) and interface traps. Through our theoretical consideration, we concluded that the interface trap density is about 1015 eV-1 cm-2 at MALI/metal contacts because the low MIGS density of about 1013 eV-1 cm-2 obtained from a theoretical equation makes little contribution to the interface state density of 1015 eV-1 cm-2 obtained from the linear fitting between the metal work functions and the EWFs.