Effect Of Tungsten And Zinc Doping On Phase Transition Performance Of VO₂ Film

Phase-change materials(PCMS)are of great application value in semiconductor industry.PCMS can be used to manufacture controllable semiconductor and optical devices.VO₂ is a substance that can undergo a reversible first phase transition at 68degrees Celsius(MIT).The phase transition of VO₂ is characterized by a sudden change in conductivity,5 orders of magnitude in bulk materials changing,and a great change in near-infrared light transmittance and refractive index.Intelligent Windows made of VO₂ can keep indoor temperature relatively constant with high efficiency and low energy.However,as a coating for intelligent Windows,VO₂ film currently has low visible light Tlum value,yellowness of the film itself,and Tc is 68°C,which is higher than the room temperature,making daily application a long way to go.This paper intends to change the Tc and properties of VO₂ films by doping W and Zn in the film.This paper designed a series of deposition parameters of the VO₂ film deposition by,using X-ray diffractometer(XRD)and atomic force microscope(AFM)of VO₂thin film had been used to characterize the phase composition and surface finish,and explore the optimal parameters of the laser energy deposition of VO₂ thin film is 450m J,deposition temperature is 600?,pulse count to 8000,oxygen pressure of 0.01mbar,pulse frequency of 2hz,t-s distance of 45 mm.The pure phase and doped VO₂ films were prepared by using the deposition parameters of the explored deposited VO₂ films,and the structural properties of the doped films were characterized by XRD.Increasing doping concentration,the membrane of surface compressive strain decreases,smaller grain size and film have taken place in the Raman spectra of a certain degree of deviation,the migration of the larger two peak at 199cm^-1(V-V)about the Raman peaks from the offset to 194cm^-1,199cm^-1,621cm^-1(O-V)about the Raman peak from 621cm^-1to 612cm^-1 migration,verify the film the lattice distortion.To delve into the doping concentration on the change of the electrical performance of VO₂ thin film,using the PPMS measured W_xZn_xV_1-2xO₂ film and W_xV_1-xO₂ delivered 2 thin film resistivity changes with temperature,the relationship between get W_xZn_xV_1-2xO₂ thin-film doping concentration,the higher the phase change temperature,the smaller the doping densitt increases 1%,phase change temperature drop 16.67 K,and reduce the size of under room temperature,phase change of the film hysteresis(?H),down from 6.57 K to 4.51 K,But the membrane phase change amplitude(?A)and temperature factor of resistance(TCR),respectively,have 2 and 1 order of magnitude of the decline,but compared with W_xV_1-xO₂ delivered 2 thin film,the same concentration of W_xZn_xV_1-2xO₂ delivered A thin film of the phase change temperature difference is less than 2%,2 phase transition performance increased by more than 50%.The influence of doping on the optical properties of the thin film was studied,and the optical properties of the thin film were measured by ellipsometer.It was found that the transmittance of the thin film to visible light increased by 39%after doping,and the transmittance spectrum of different concentrations could blue shift the light band,indicating that the defect of the thin film being yellow at room temperature was improved.