Au/SiO2纳米复合薄膜的微结构及光吸收特性研究

用多靶磁控溅射技术制备了Au/SiO₂纳米多层薄膜.利用透射电子显微镜以及吸 收光谱对Au/SiO₂复合薄膜的微观结构、表面形貌及光学性能进行了表征和测试 .研究结果表明：单层Au/SiO₂薄膜中Au沉积时间小于10s时，分散在SiO_{2< /sub>中的Au颗粒随Au的沉积时间的延长而增大；当沉积时间超过10s后，Au颗粒的尺寸几乎 不随沉积时间变化，但Au颗粒的形状由网络状结构变为薄膜状结构.［Au(t1关键词： 尺寸效应 纳米复合薄膜 吸收光谱 有效媒质理论}

Microstructure and photoabsorption of Au/SiO2 nano-composite films

Au/SiO₂ nano-composite multilayer thin films were prepared by magnetr on plasma sputtering. The microstructure, morphology and optical properties were investigated using transmission electron microscopy and absorption spectra. The Au particles dispersed in the SiO₂ matrix of one single Au layer gre w with increasing deposition time in the initial time interval of less than 10s. No obvious change in the size of Au particles was observed in the films deposit ed for more than 10s, however, the shape of Au particles changed. The optical ab sorption peaks due to the surface plasma resonance appeared at a wavelength of 5 40—560nm for ［Au_(t1)SiO₂₍₆₀₀₎］×5 thin films . The intensity of the absorption peak increased with increasing deposition time . Influence of the Au particle shape on the position and intensity of plasma res onance absorption peak was also discussed. The optical absorption spectra of Au/ SiO₂ thin films are well in agreement with the theoretical optical ab sorption spectra calculated from reformed Maxwell-Garnett effective medium theor y.