Flexible SnO₂–MoS₂ based memristive device exhibiting stable and enhanced memory phenomenon

Abstract

Flexible non-volatile memory devices have been gaining interest in expanding the digital data storage world. Due to the burgeoning advancement in the healthcare industry, the Internet of Things, and wearable electronics, the demand for ultra-thin, low-power, and flexible memory is increasing. Further, the advancement of synthesis procedures for two-dimensional nanomaterials having better optical, electrical, and mechanical strength with flexibility has fuelled the flexible memory device area, as commonly used flash memory is approaching its physical limit. In this context, the present work reports the flexible resistive switching memory device based on pure molybdenum disulfide (MoS2) and tin oxide (SnO2) based nanocomposite powder synthesized using the simple hydrothermal process. The nanocomposite formation was characterized using x-ray diffraction and Raman spectroscopic techniques. The memory device was fabricated by spin-coating the pure MoS2, pure SnO2, and MoS2–SnO2 nanocomposite film over the ITO-PET flexible substrate. The device was completed by thermally evaporating the thin Al layer through a shadow mask. It was found that MoS2–SnO2 based memory devices exhibited improved switching performance having a higher I ON/I OFF ratio, and lower switching voltage in comparison to pure MoS2 and pure SnO2-based devices (I ON/I OFF ratio ∼100, V = 0.5 V). Furthermore, to check the stability and cyclic performance of the fabricated device, the retention and endurance test was also performed, and the MoS2–SnO2 device retained the HRS and LRS states up to 2 × 103s and showed stable performance up to 100 switching cycles without much degradation, respectively. It should be mentioned that the presently proposed ReRAM device based on SnO2 and MoS2 with flexible and low-power features had excellent potential for use in the wearable device industry.