Low voltage & controlled switching of MoS₂-GO resistive layers based ReRAM for non-volatile memory applications

Abstract

Emerging information technology and data deluge foster the unprecedented demands of higher chip density, clocking speed, data storage and lower power dissipation for on-chip non-volatile memories (NVMs). Here, two types of metal-insulator-metal (MIM) based NVM structures were fabricated and demonstrated involving controlled functionalization of molybdenum disulfide (MoS2) and graphene oxide (GO) nanocomposite as a resistive switching layer. The first type of device constitutes Aluminum (Al) top and bottom electrode resulting in the Al/MoS2-GO/Al structure. While the second type of device uses Al top electrode and Indium Tin Oxide (ITO) bottom electrode resulting in Al/MoS2-GO/ITO. The current-voltage (I–V) characteristics for fabricated Al/MoS2-GO/Al and Al/MoS2-GO/ITO MIM structures exhibited considerable ION/IOFF ratio of ∼102 (SET and RESET state at 0.5 V and −0.4 V) and ∼101 (SET and RESET state at 0.3 V and −1 V), respectively. The I–V characteristics for Al/MoS2-GO/Al MIM structure showed low voltage switching, substantial memory retention ∼104 s and endurance for up to 25 cycles. The low voltage and controlled switching operation for Al/MoS2-GO/Al MIM structures may be attributed to the presence of a large number of oxygen vacancies, defects in MoS2-GO, promoting enhanced charge hopping via interfacial oxide at MoS2-GO/Al interface as compared to MoS2-GO/ITO.