Research On Growth And Photoelectric Properties Of VO₂/MoS₂ Heterosturecture

Molybdenum disulfide and vanadium dioxide are very representative and highly applicable semiconductors.The unique layered structure of molybdenum disulfide is similar to graphene.While possessing many excellent properties similar to graphene,molybdenum disulfide not only has The regulated energy band gap can be prepared as a few-layer two-dimensional material,and molybdenum disulfide is the main component of molybdenite,and its natural reserves are rich,which makes it indispensable in the field of electronic devices and optoelectronic devices.Materials;and vanadium dioxide has excellent conductivity,and has two crystal structures of monoclinic phase and tetragonal phase,but when the temperature changes,vanadium dioxide has the unique property of reversible phase change with temperature changes,making it in The field of making temperature-controlled films shines.Both of these materials have very valuable development prospects and are suitable for the preparation of heterojunction materials,so this paper will focus on molybdenum disulfide and vanadium dioxide,and study the growth and preparation processes of the two materials.After obtaining a high-quality thin film,a heterojunction of molybdenum disulfide and vanadium dioxide is prepared.At the same time,several models of the two materials are calculated through simulation software to obtain various theoretical properties of molybdenum disulfide and vanadium dioxide.Then a detector with a heterojunction as the core was prepared.The main research contents are as follows:First of all,the topic started with the growth process of molybdenum disulfide and vanadium dioxide.First,the use of radio frequency magnetron sputtering to grow vanadium dioxide on a silicon substrate,a single variable was selected in groups to study the sputtering power,sputtering time and argon The influence of gas flow on the crystal quality and photoelectric performance of the thin film was tested by XRD after obtaining each group of samples.The analysis results showed that the optimal process parameters under the experimental conditions were 100 W sputtering power,60 min sputtering time and 24 sccm A good argon flow rate,and then based on the vanadium dioxide film,the same use of magnetron sputtering to grow molybdenum disulfide film,the same group control variables and XRD test analysis to obtain the optimal process parameters under the experimental conditions of 200 W sputtering Power,1 Pa sputtering power and 40 min sputtering time,and then combined with two conclusions to prepare a vanadium dioxide disulfide molybdenum heterojunction and characterize the photoelectric performance,the heterojunction exhibits the light absorption of the two materials.In the simulation test,the calculation results of the small-layer molybdenum disulfide model show that the band gap of the two-dimensional molybdenum disulfide decreases with the increase of the number of layers,and there is an absorption peak at 238.5 nm,while the two-phase vanadium dioxide model The composition of its Fermi level is revealed.Under the stress of different crystals,?100?the stress in the crystal direction narrows the band gap,?001?the stress in the crystal direction widens the band gap,?110?The stress in the crystal direction makes the forbidden band width widen first and then narrows.When the stress reaches 30%,the forbidden band width drops sharply and even approaches 0 e V,while the?111?crystalline pressure will obviously widen the forbidden band width.The stress increasing material changes from direct band gap to indirect band gap.Finally,based on the previous experiments and simulations,a ultraviolet detector with a heterojunction as the core was prepared.The detector has two peak responses corresponding to MoS₂ and VO₂.The response is found at 400-600 nm and 850 nm,respectively.It is 0.52×10-2 A/W,and the external quantum efficiency at the response peak is 2.8%,which reveals that the VO₂/MoS₂ heterojunction detector does have performance improvement and certain research value.