采用粉末靶射频磁控溅射方法制备非晶Al₂O₃薄膜, 分析了溅射工艺参数对Al₂O₃薄膜微观结构、表面形貌、光学性能的影响规律及机理, 并探究其抗菌特性. 研究结果表明: 增加氧通量、降低溅射功率和缩短溅射时间均会减小非晶Al₂O₃薄膜颗粒度与粗糙度, 同时也降低薄膜的沉积速率; 并且, 氧通量的增加和溅射时间的缩短均会使非晶Al₂O₃薄膜禁带宽度变宽(最大值可达4.21 eV)、透光率增大(超过90%); 光照条件下非晶Al₂O₃薄膜24 h抗菌率最高可达98.6%, 体现出了较好的光催化抗菌性.

Al₂O₃ thin films are widely applied in mechanic, optic and electronic fields due to their excellent properties. Among many deposition techniques, magnetron sputtering is regarded as one of the most practical approaches for preparing Al₂O₃ films. In sputtering process, the use of powder targets could offer the advantages of easily variable and controllable composition and low cost. However, it is not yet known well enough how to determine sputtering parameters, microstructure and properties of Al₂O₃ films from powder targets. In this work, Amorphous Al₂O₃ films were prepared by radio frequency magnetron sputtering process in which high pure Al₂O₃ powder was used as the target material. The effects and mechanism of the sputtering parameters on the microstructures, surface morphology and optical properties of amorphous Al₂O₃ films were analyzed by XRD, AFM, surface profile, UV-Vis spectroscopy and so on. Considering used as the packaging material, the antimicrobial performance of amorphous Al₂O₃ films was also studied. The experimental results showed that: increasing the oxygen flow, decreasing the sputtering power and shortening the sputtering time could make the particle size and roughness of amorphous Al₂O₃ films lower while depressing the deposition rate of amorphous Al₂O₃ films. Moreover, the increase of the oxygen flow and decrease of the sputtering time would widen the band gap which the maximum was up to 4.21 eV, and heighten the transmittance of the visible light which was beyond 90%. The antibacterial rate of amorphous Al₂O₃ films under the natural light after 24 h was up to 98.6%, which reflected the photocatalytic characteristics of the antimicrobial mechanism.