Vertically oriented 2D layered perovskite-based resistive random access memory (ReRAM) crossbar arrays

Abstract

Resistive random-access memory (ReRAM) based on 2D layered perovskites have recently emerged as a new class of data storage devices, and the switching materials used in these devices have attracted extensive attention in recent years. There is a certain amount of variability in ReRAM owing to the stochastic nature of the formation and rupture of the conductive path, causing failure of the switching operation in the memory array. In this work, we fabricated both randomly and vertically oriented PEA2MA4Pb5I16-based ReRAM devices and conducted comparative studies of their switching variability. We demonstrated the formation of vertical alignment in PEA2MA4Pb5I16 films using methylammonium chloride (MACl) additives. Thereafter, the fabrication of 8×8 ReRAM crossbar arrays by patterning perovskites (∼600μm) and electrodes (line width ∼ 5 μm) using photolithography and e-beam lithography is demonstrated, and the resistive switching characteristics of both samples are discussed. Both cycle-to-cycle and device-to-device switching uniformity were improved in the vertically oriented film-based ReRAM devices, which can be explained by the narrow distribution of the energy barriers for VI migration owing to the vertically aligned charge transport path. These results suggest that vertically oriented 2D layered perovskites have great potential in ReRAM devices with improved switching uniformity.