(1. 三峡大学 材料与化工学院 无机非金属晶态与能源转换材料重点实验室，宜昌 443002； 2. 广西新未来信息产业股份有限公司，北海 536000)
摘 要: 以Ga2O3掺杂量(质量分数)为3%的ZnO-Ga2O3混合粉体为原料，采用热压烧结法制备GZO陶瓷。通过XRD、SEM、阿基米德排水法和四探针法对烧结试样的物相组成、显微结构、密度和电阻率等进行分析表征。结果表明：外加压力能有效降低GZO陶瓷烧结致密化温度；当外加压力为18 MPa时，随烧结温度升高，烧结体的密度和电导率增大；当烧结温度达1150 ℃时，烧结体密度和电导率达到最大值；但当烧结温度继续增大时，由于晶粒粗化和Zn元素挥发导致试样中气孔长大，试样致密度与导电性呈下降趋势。此外，ZnO-Ga2O3混合粉体在烧结温度较低时(1050 ℃)，Ga2O3与ZnO固相反应生成ZnGa2O4立方尖晶石相；随着烧结温度升高，ZnGa2O4将与ZnO继续反应，生成与ZnO六方纤锌矿结构呈共格关系的复杂化合物ZnxGa2Ox+3，并且化合物化学式中x值随着烧结温度的升高而增加，化合物晶体结构逐渐接近ZnO六方纤锌矿结构。
关键字: GZO陶瓷；热压烧结；烧结温度；致密化；固相反应
（1. Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials, College of Materials and Chemical Engineering, China Three Gorges University, Yichang 443002, China; 2. New Future Information Industry Co., Ltd., Beihai 536000, China）
Abstract:Gallium-doped zinc oxide ceramic (GZO) was prepared by hot-pressing using 97% ZnO and 3% Ga2O3 mixture powder as raw materials. The phase structure was measured by X-ray diffraction. The microstructure of ceramic was observed by SEM. The density of ceramic was measured by Archimedes method. The electrical property of ceramic was investigated by four-point probe method. The results show that sintering temperature is reduced effectively by external pressure during sintering. With increasing sintering temperature, the relative density increases and electrical resistivity decreases at 18 MPa. The maximum relative density and the lowest resistivity of ceramic are achieved at 1150 ℃. The density and electrical conductivity deceases as temperature rising above 1150 ℃, due to grain coarsening and Zn volatilization caused by porosity growth. In addition, ZnGa2O4 cubic spinel phase is synthesized by solid-phase reaction of Ga2O3 and ZnO at 1050 ℃. As the temperature further increases, ZnGa2O4 reacts with ZnO to form ZnxGa2Ox+3 which has coherent relation with hexagonal wurtzite structure of ZnO, while x rises with temperature increasing, the structure of the complex compounds become more similar to that of ZnO.
Key words: GZO ceramic; hot-pressing; sintering temperature; densification; solid-phase reaction
