摘要
用多靶磁控溅射技术制备了Au/SiO_2纳米多层薄膜.利用透射电子显微镜以及吸收光谱对Au/SiO_2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/SiO_2薄膜中Au沉积时间小于10s时,分散在SiO_2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)SiO_2(600)]×5多层薄膜在540—560nm波长附近有明显的表面等离子共振吸收峰,且吸收峰的强度随Au的沉积时间增加而增强.基于修正后的Maxwell-Garnett(M-G)有效媒质理论,讨论了金属颗粒的形状对等离子共振吸收峰的峰位和强度的影响.模拟的吸收光谱与实验吸收光谱形状、趋势及吸收峰位相符合.
Au/SiO2 nano-composite muhilayer thin films were prepared by magnetron plasma sputtering. The mierostrueture, morphology and optical properties were investigated using transmission electron microscopy and absorption spectra. The Au panicles dispersed in the SiO2 matrix of one single Au layer grew with increasing deposition time in the initial time interval of less than 10 s. No obvious change in the size of Au particles was observed in the films deposited for more than 10 s, however, the shape of Au panicles changed. The optical absorption peaks due to the surface plasma resonance appeared at a wavelength of 540--560 nm for [ Au （tf ） SiO2（600） ] × 5 thin films. The intensity of the absorption peak increased with increasing deposition time. influence of the Au particle shapc on the position and intensity of plasma resonance absorption peak was also discussed. The optical absorption spectra of Au/SiO2 thin films are well in agreement with the theoretical optical absorption spectra calculated from reformed Maxwell-Garnctt cffcctive medium theory.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2006年第4期2078-2083,共6页
Acta Physica Sinica
基金
国家自然科学基金(批准号:50572008)
教育部新世纪优秀人才支持计划(批准号:NCET-04-0105)
辽宁省科学技术基金(批准号:20042157)资助的课题.
关键词
尺寸效应
纳米复合薄膜
吸收光谱
有效媒质理论
size effect, nano-composite film, optical absorption spectra, effective medium theory
