Preparation Of Zinc Aluminum Oxide Targets By Sol-Gel Method

The performance of AZO (aluminum doped zinc oxides, Al-ZnO) targets is one of the important factors which affets the properties of thin films prepared by magnetron sputtered method. Pressureless sintering, hot isostatic pressing sintering and vacuum sintering are the main methods for preparation of AZO targets. AZO targets prepared with hot isostatic pressing sintering method and vacuum sintering method have better performance, but the size and shape of theses targets have been limited, and the complex processing leads lower efficiency and higher production cost. Aluminum doped zinc oxides powder prepared sol-gel method has better uniformity of composition, better controllability of shape and size, and even lower production cost by using inorganic materials, therefore it has high applicable value.In this paper, aluminum doped zinc oxides powders has been synthesized by sol-gel method and AZO target with low resistivity and high relative density prepared by pressureless sintering route, effects of complexing agent, reaction temperature, pH value and drying temperature on the morphology of powder, effects of ball milling and sintering on the properties of AZO target have been investigated, and the comparison between as-synthesized target and that prepared by solid state reaction method has been finished, too. The results show that powder with better sintering performance can be obtained by control the parameters of sol-gel method, ball milling can reduce the agglomeration of powder and increase the relative density of target. With the increasing of molding pressure, the relative density of target also increases first and then reduces, but the resistance has the reverse effect. With the increasing of sintering time, the crystal grain size increases rapidly, the relative density increases slowly and the resistivity improve unobvious. And at last, AZO target with the relative density of 99.2% and resistivity of 2×10^-2Ω·cm has been obtained when molding pressure is 2MPa and sintered at 1250℃for 1h.