Performance Optimization Of Micro-Nano Devices Based On Two Dimensional Layered Tin Selenide

Two-dimensional layered materials refer to a type of nanomaterials,the thickness of which is at the level of one single atomic layer.Compared with bulk materials,two-dimensional layered materials have unique and excellent electrical,optical,and mechanical properties,which provide a material basis for the development of new functional devices.Two-dimensional tin diselenide（SnSe₂）is one of the semiconducting layered materials,with anisotropic electrical and optical properties,indicating important research and application value in the fields of photoelectric detection and thermoelectricity.However,due to the high carrier concentration of SnSe₂,which is about 100 times that of the ordinary two-dimensional layered materials.Therefore,functional devices based on SnSe₂ cannot be turned off,leading to the problems such as inability to achieve logic functions or high power consumption.In order to solve this problem,this paper studies the mechanism of two CMOS compatible semiconductor processes to effectively control the SnSe₂ carrier concentration,including rapid annealing and plasma treatment,which significantly improves the performance of SnSe₂ field-effect transistors and other functional devices.The main research contents are as follows:1.The mechanism of SnSe₂ carrier concentration modulation by rapid annealing process in air environment is studied.It is discovered that the oxidation of SnSe₂ materials by oxygen in the air under a high temperature environment can produce the effect of p-type doping.The catalytic effect of gold on this reaction is also revealed.Through this processing method,the on-off ratio of the SnSe₂ field effect transistor is effectively increased to over 10³.2.The mechanism of modulating SnSe₂ carrier concentration by plasma treatment process in N₂O gas environment is studied.Based on the research of annealing in the air environment,the use of N₂O plasma gas,which is more oxidative than high-temperature air,under the catalysis of gold,achieves more efficient oxidation and carrier control of SnSe₂ materials.3.The plasma treatment process under N₂O gas environment improves the performance of SnSe₂-based functional devices.A broad-spectrum photodetector based on the SnSe₂/WSe₂ heterojunction is prepared to simulate the function of artificial visual neurons,which realizes the highly sensitive detection and recognition of different light wavelengths.A multi-value memory based on SnSe₂-boron nitride-graphene vertical floating gate structure was prepared,and the function of multi-value storage was realized by improving the device switching ratio and using the electrical anisotropy of SnSe₂.