Strategic extended air stability of organolead halide perovskite nonvolatile memory devices

Abstract In this study, we demonstrated long-term stability in the resistive switching (RS) properties of MAPbI3 films, coated via a one-step chemical vapor deposition (CVD) method using no additives or polymers. The RS behavior of the CVD-fabricated memory devices compares favorably to that of spin-coated films; these devices exhibited reliably stable bipolar resistive switching properties for 30 days under ambient conditions, while spin-coated devices were stable for only 10 days. For further enhancement of air stability, a 20 nm-thick ZnO passivation layer was deposited on MAPbI3 via on-axis and facing-target sputtered (FTS) techniques. The resistive random-access memory (ReRAM) devices with a ZnO passivation layer deposited via FTS technique exhibited extended air stability for 3 months under ambient conditions, whereas in the case of memory devices fabricated with an on-axis sputtered passivation layer, air stability was limited to 60 days. This extended air stability can be attributed to excellent step coverage and free of plasma damage during deposition. Memory devices fabricated via the CVD and FTS methods showed no significant variations at either set or reset levels of voltage and showed favorable levels in terms of both data retention and endurance performance with storage time.