Investigation Of Low Emissivity Properties Of Fluorine And Tantalum Co-doped Tin Oxide Films

The low emissivity properties of tin oxide based transparent conductive films had important theoretical and practical value.The fluorine-doped tin oxide film?FTO?prepared by spray pyrolysis method was the research object,The low emissivity properties of the FTO film was further optimized by determining the optimum solvent.Furthermore.The tantalum and fluorine co-doped tin dioxide films were prepared by aerosol-assisted method.The effects of multi-doping on the optical,electrical and emissivity of tin-doped films were investigated.The structure,morphology,element existence and stress state of the film were characterized by XRD?SEM?AFM?XPS and Hall effect.The main findings are as follows:The FTO film prepared by using methanol as a solvent has the best integrated optical and electrical properties and the figure of merit can reach 1.646×10^-2?^-1.The transmittance in the visible light region was greater than 75%.The Hall mobility of FTO films prepared in different solvents is mainly affected by the scattering of ionized impurities.The optical band gap of the film has a maximum value of 4.06 eV,and the result is related to carrier degeneracy.When the tantalum doping concentration is 2 at.%,the TTO film has the best optical and electrical properties and a low emissivity.The tendency of preferential growth of the film is affected by the internal stress of the film.A certain concentration of tantalum doping leads to an increase in the absence of oxygen O_I in the film,and a decrease in sufficient oxygen O_II,an increase in the number of defects associated with oxygen,and an increase in the conductivity of the film.The transmittance of the film is affected by the surface roughness of the film,and the average transmittance is greater than 65%.An increase in the doping concentration results in a decrease in the transmittance.The TFTO film prepared at a doping concentration of 1 at.%has the best optical and electrical properties and a low emissivity.The prepared films all have a high transmittance?greater than 70%?,and the doping affects the surface roughness of the film,thereby affecting the transmittance of the film.The XPS study of the film proves the existence state and bonding mode of fluorine and tantalum.It shows that the fluorine element and the tantalum element have successfully entered the tin dioxide lattice,which serves to provide carriers.The Raman picture shows that the doping of fluorine has a significant effect on the oxygen vacancies in the tin dioxide.