Cu-MgF_2纳米金属陶瓷薄膜的微结构及吸收光谱特性研究

Microstructure and Absorption Spectrum of Cu-MgF_2 Cermet Film

对用蒸发技术制备的Cu -MgF2 纳米金属陶瓷薄膜微结构及吸收光谱特性进行了研究。微结构分析表明薄膜由fcc -Cu纳米晶粒镶嵌于主要呈非晶态的MgF2 基体中所组成 ,晶粒的平均粒度约为 1 4～ 1 6nm。Cu -MgF2 纳米金属陶瓷薄膜在 2 0 0～ 80 0nm波段内的吸收光谱表明 :随着波长增加 ,吸收减小 ;Cu纳米晶粒的表面等离子共振吸收峰出现于 560nm处 ;短波长区呈现较强的Cu的带间跃迁吸收。用三维弥散系统的Maxwell-Garnett理论对Cu -MgF2 复合体系的实验吸收光谱特性作出了解释。

The microstructure and absorption spectrum of Cu-MgF 2 cermet film prepared by evaporation were investigated. The results show that Cu-MgF 2 cermet film is composed of mainly amorphous MgF 2 matrix with embedded fcc-Cu nanograins, with a mean size of 14～16nm. The results also show that the absorption of the film, in the range of 200～800nm, decreases as the wavelength increases. Surface plasmon resonance absorption peak at 560nm and interband transition absorption of Cu in shorter wavelength range were observed. By employing Maxwell-Garnett theory for a 3D dispersion system, the experimental absorption characteristics were interpreted.