Preparation And Photoelectric Properties Of Composite ITO Films

As an N-type transparent conductive oxide film,ITO film has been widely used for its high transmittance and good electrical conductivity in visible region.Because of its unique photoelectric characteristics,it has been used in many scientific and technological applications,such as flat panel display,light emitting devices,sensors and solar cells and other fields.At present,with the increasing demand for high definition,large size and exquisite display panel,higher requirements are put forward for ITO conductive film.When the thickness of ITO film increases,the conductivity of ITO film increases obviously,but the transmittance of visible light decreases greatly.Therefore,it is particularly important to adjust the contradiction between visible light transmittance and electrical conductivity of ITO film.In order to improve the photoelectric performance of ITO film and adjust the contradiction between visible light transmittance and electrical conductivity of ITO film,this thesis carried out research on the preparation and performance of composite ITO film.The main research work and results are as follows:（1）Porous ITO films using PMMA as template were prepared by sol-gel method and breath pattern method.The conductivity of porous ITO film was improved,and the transmittance of visible light was significantly higher than that of non-porous ITO film.However,in the process of preparing porous ITO film,it is found that the concentration of ITO colloid,the concentration of PMMA template and the annealing mode of ITO film all affect the photoelectric properties of the prepared ITO film.When the annealing temperature was set to 200℃,the porous ITO film obtained a relatively complete porous structure.Compared with other annealing temperatures,the visible light transmittance of the film was 95.4%.When the concentration of ITO is 0.2 mol/L,the transmittance of porous ITO film is 96.8%.When preparing the porous PMMA template,the amount of PMMA has a great influence on the pore structure of the film.When the concentration of PMMA is 0.02 g/mol,the prepared ITO can obtain a good pore structure from the template,with a high transmittance of 94.7%.Under the optimized conditions:ITO gel concentration of 0.4 mol/L,PMMA concentration of 0.02 g/mol ITO film,at 300℃to the furnace,the visible light transmittance is 94.7%,the film quality factor is 1.5×10^-3Ω^-1.（2）ITO/Ag/ITO multilayer composite films based on TCO/Metal/TCO multilayer composite films were prepared by magnetron sputtering.The electrical conductivity of ITO film was improved by inserting metal Ag film into ITO film.By adjusting the sputtering process,the position of Ag film in ITO film,the sputtering temperature of bottom ITO film and the sputtering temperature of top ITO film and middle Ag film,the influence of the preparation process of ITO/Ag/ITO multilayer composite film on its photoelectric properties was investigated.Under the optimized conditions,the prepared ITO/Ag/ITO multilayer composite film achieves high electrical conductivity when Ag film is in the middle layer of ITO film and the sputtering temperature of bottom ITO film is 400℃,while the sputtering temperature of top ITO film and Ag film is 120℃。The square resistance of the prepared ITO/Ag/ITO film is 3.6Ω/sq,and the average transmittance of the film in the visible light range is 80%.