Studies Of Fabrication And Performance Of Two-dimensional Memristors Based On Novel Structures

Memristors have attracted tremendous interest for its unique application in the field of high-density memory and neuromorphic computing after been discovered at2008.However,despite tremendous efforts and works devoted recent years,the high operation voltage,poor stability and large device variability remain key limitations for its practical application,and could be partially attributed to the un-optimized interfaces between electrodes and the channel material.In the early preparation of memristors,the integration between the channel material and the metal electrode requires the processes such as physical deposition and wet etching.During this period,the channel material tend to be doped and destroyed by high-energy particles,and chemically treated by the etching reagent.these effects will influence the electrical performance of the device.Here,for the first time,we demonstrate a van der Waals memristor by physically sandwiching pre-fabricated metal electrodes on both sides of two-dimensional channel material.The atomically flat bottom electrode ensures the intimate contact between channel and electrode(hence low operation voltage),and the vd W integration of top electrode could avoid aggressive fabrication processes(e.g.,sputtering,lithography)directly applied on channel material,improving device stability.Together,we demonstrate memristor arrays with high integration density of 10¹⁰/cm²,high stability,as well as lowest set/reset voltage of 0.12 V/0.04 V,which is a record low value in all2D based memristors,as far as we know.Furthermore,detailed characterizations are conducted to confirm the improved memristor behavior is the result of optimized metal/channel interfaces.Our study not only demonstrates robust and low voltage memristor based on two-dimensional materials,but also provides a general electrodes integration approach for other memristors(such as oxide based memristors)that are previously limited by non-ideal contact integration,high operation voltage and poor device stability.