Preparation And Research On AZO Solar Thin Film

AZO thin films were deposited on transparent glass substrates by magnetron sputtering in two ways, which are Zn, Al metal target direct current sputtering and97:3（wt%） ceramic target RF sputtering.Then the films were annealed to improve the structure.Finally, X-ray Diffraction（XRD）,Four point probe,Ultraviolet spectrophotometer and Scanning electron microscope（SEM） were used to test surface quality, crystalline quality, electrical properties and optical properties of films.The main parameters are the ratio of oxygen and argon, Al content, Ar pressure, annealing time and temperature. Analyzing the performance of the films produced by changing the parameters of the films.Experimental results:AZO thin films were prepared by Metal double target sputtering system. When O₂/Ar=0.35, the comprehensive performance of the film is excellent, transmittance is92%, the resistivity is 5.6×10^-3 ?.cm.The oxygen content has great influence on the photoelectric properties of the films.In the experiment, with the increase of oxygen argon ratio（0.25-0.8 range）, the transmittance of the films increased from 85% to92%, and the electrical resistivity increased from 5.6×10^-3?.cm to 1.4×10-2?.cm.The optical performance of AZO thin films were not affected by the content of Al, and the transmittance of all samples was above 85%.However, the crystalline quality and conductivity of the thin film can be changed.When Wt（Al）=1.2%, the grain size is the largest, and the crystal performance is excellent. When the content of Al is 1.4%, the resistivity is 4.2×10^-3?.cm which is the lowest.The properties of the films was improved by annealing treatment.The appropriate annealing process can refine the grain and make the AZO thin films recrystallization.The film crystallization is improved, and the photoelectric properties are enhanced.In a certain range, the higher the annealing temperature is, the better photoelectric performance the films are, and the annealing time also has a great influence on the film properties.In this experiment, by comparing different annealing temperature and time,when the AZO films were annealed for 1²h at 450℃ whichwere prepared by metal target sputtering, the photoelectric performance was the best.The transmittance and resistivity were 92% and33.6 10.cm-′ ?.AZO thin films were prepared by RF sputtering of ceramic target.In the sputtering process, O₂ addition is beneficial to the oxygen species to be fully combined with Zn, which is beneficial to improve the optical properties of AZO thin films.In this experiment,transmittance of all samples is relatively high,reaching93%.In the case of oxygen barrier, transmittance of AZO thin films reached 90%,under this condition, the film resistivity is the lowest,reaching33.2 10.cm-W′, overall performance is the best.Argon gas pressure is an important factor affecting the electrical properties of AZO thin films.Under the condition of no oxygen in this experiment, with the increase of the argon gas pressure, from 0.1Pa to 1.5Pa,the intensity of the diffraction peak（002） is smaller and smaller, the resistivity increases gradually.However, the transmittance has no obvious effect.Annealing treatment also has a great influence on the AZO thin films prepared by RF sputtering of ceramic target.It is similar to the effect of AZO thin films prepared by metal target sputtering.The AZO films which were annealed for 1h at 420℃ have the best photoelectric performance.