Fabrication And Resistance Characteristics Of Memristor Devices Based On Two-dimensional Layered MoTe₂

In the age of big data,a large amount of data are produced every year.The large amount of data requires the next generation of non-volatile memory（NVM）technologies to have large storage and high speed.Among them,memristors store and output information by switching between different resistance states,and the scalable nanoscale dimension of memristor makes it possible for high density and large scale integration.The memristor has sub-nanosecond switching speed,low programming energy consumption,and long write/erase endurance,and is expected to solve the key problem of traditional computer architecture.In addition,it can be used to mimic the synaptic connections in the（biology）brain,which has attracted increasing attention in neuromorphic computing.The 2D materials as functional materials and structural materials are expected to make the nanoscale electronic devices with smaller size,lower power consumption and higher efficiency.Currently,many two-dimensional materials have been applied in memristor.In this paper,multi-layer MoTe₂ was prepared by mechanical exfoliation method,and the main research contents are as follows:1.the Ag/MoTe₂/Au vertical structure device was prepared by multi-layer MoTe₂material.The typical electrical characteristics of the Ag/MoTe₂/Au vertical structure device were explored.The device showed good cycle endurance performance and could be prepared repeatedly,with fast switching speed（40 ns）and closing speed（140 ns）.It shows excellent retention characteristics at different compliance current（100μA,300μA and 500μA）and has multilevel storage performance.In addition,the device has a low operating power consumption（4.48 p J）.Conducting atomic force microscopy（C-AFM）and temperature-dependent resistance measurement confirm that the formation and rupture of Ag conductive filament is responsible for the repeatable resistive behavior of the device.Finally,we prepared the logical array based on Ag/MoTe₂/Au vertical structure device,realized a variety of logical operation functions（AND,OR,XOR,NAND and IMP）,and verified the feasibility of integrated storage and computing.2.the multi-layer MoTe₂ material obtained by mechanical exfoliation method was used to prepare Au/MoTe₂/Au planar structure devices.Since MoTe₂ material is easy to be oxidized,we doped MoTe₂ material by being heated in the air and oxygen plasma treatment,and introduced oxygen defects into MoTe₂ material.The device exhibited two different volatile electrical properties of enhancement and inhibition,and the mechanisms of these two electrical properties are analyzed and explained.The dependence of the response current of Au/MoTe₂/Au planar device on the width,amplitude,number and frequency of electric pulses is investigated.In addition,the band gap of MoTe₂ material is about 1.0 e V,so,the device has optical response from visible to near-infrared region.Therefore,we further explored the optical properties of Au/MoTe₂/Au planar structure devices from visible to ultraviolet（VIS-UV）and near infrared（IR）wavelengths.The relationship between the optical response current and the time,intensity,number and frequency of optical pulses is explored through the regulation of optical signal,and the synaptic learning behavior is simulated.