Fixed-point Growth Of Two-dimensional Materials And Its Photoelectric Test

Molybdenum disulfide(MoS₂)is a typical representative of the two-layer material family.Due to its internal structure is similar to graphene,it not only retains the excellent electrical,optical and mechanical properties of graphene.At the same time,it has an adjustable band gap of 1.2?1.8 e V,and the band gap can be adjusted by changing the thickness,so it has a unique advantage in the preparation of electronic devices(such as field effect tubes,light-emitting diodes,photodetectors).With the rapid development of science and technology,to integrate a large number of components on the chip,traditional silicon material can produce the problem such as the leakage and poor heat dissipation,and the two-dimensional structure of molybdenum disulfide monolayer film thickness is always less than 1 nm,at the same time with optical,mechanical and electrical properties of graphene,make its applications in integrated circuits and nano electronic devices on possible.In addition,Mo and S elements are abundant in nature,which makes MoS₂ have a broader prospect in the field of optoelectronic devices.(1)Dc sputtering+reactive ion etching+CVD method:In the environment of 99%purity argon,high-purity Mo target is sputtered.With the enhancement of sputtering time and sputtering power,Mo film becomes compact and its crystal structure is relatively stable.Then the sample was covered with a self-made mask and put into RIE reactive ion etching machine.SF₆ was used to etch the metal Mo.Then the prepared Mo film is put into a tubular furnace for vulcanization.The reaction temperature was set at 600?,700?and 800?,respectively.The carrier gas was Mo film of sulfide metal in Ar environment.When the temperature reached 800?,MoS₂ phase was the purest.In the vulcanization operation,the mass of S powder is 0.8g,which can not only fully vulcanize Mo,but also avoid the pollution caused by sulfur vapor flowing into the air.(2)Use magnetron sputtering+photolithography+CVD high temperature annealing:first use photolithography to prepare the pattern we want on the silicon oxide,and then put the patterned silicon wafer into the magnetron sputtering coater Vacuum sputtering is performed on the top,the target material is MoS₂ target material,after the sputtering time is fixed and the power is fixed,it is put into the tube furnace for annealing.What is prepared at this time is the patterned MoS₂ we want.Compared with Mo vulcanization,there is no need to use sulfur powder for vulcanization after changing to MoS₂ target material.The main content of this paper is the fixed-point preparation of molybdenum disulfide.The secondary content is to apply the prepared MoS₂ to the photoelectric field to test its photoelectric performance,proving that the fixed-point growth of molybdenum disulfide film in this experiment has a wide range of application scenarios in practical life.In this paper,rf magnetron sputtering and MoS₂ target are used to prepare three groups of thin film samples by controlling the sputtering time,annealing temperature and sputtering power respectively by controlling single variable method.The films were characterized by scanning electron microscopy(SEM),X-ray diffraction(XRD),atomic force microscopy(AFM),Raman spectrometer and UV-Visible spectrometer.The initial results showed that the sputtering pressure was 1.0 Pa,the sputtering power was 30 W,the sputtering time was 30 min and the annealing temperature was 500?.At this time,the crystal quality and surface morphology of the film are the best.Then the film with good performance is made into a photodetector,and the photoelectric performance of the film can be analyzed through the exploration of the photodetector.