表面等离子体共振增强ZnO/Ag薄膜发光特性研究（英文）

Enhanced ultraviolet emission due to surface plasmon resonance in ZnO/Ag

为了提高氧化锌光致发光强度，以磁控溅射氧化锌／银复合薄膜为研究对象，系统地研究了氧化锌薄膜的光学性质。实验中首先在硅衬底上用射频磁控溅射的方法沉积氧化锌／银复合薄膜，作为对比，同时沉积了一层氧化锌薄膜。通过扫描电子显微镜和原子力显微镜对样品的形貌及成份进行表征，并且在室温下测试样品在300～800nm波长范围内的光致发光光谱。实验结果表明：所制得样品为均匀分布的氧化锌纳米薄膜，纯氧化锌光致发光光谱结果显示有波长位于378nm左右的紫光、470nm左右的蓝色发光峰存在，加入银薄膜后，氧化锌可见光区和紫外光区的光致发光光谱强度均有所增强，而且紫外光峰位出现了红移。实验结果结合样品吸收谱对光致发光机理的分析作了进一步的分析。

To improve the photoluminescence intensity of ZnO, the optical properties of ZnO/Ag structures were systematically investigated. The radio-frequency magnetron sputtering technique was adopted to deposit ZnO and Ag thin films on Si substrates. The optical properties of ZnO/Ag structures that significantly different from those of pure ZnO thin films at different sputtering time were demonstrated in detail. The photoluminescence intensity of ZnO/Ag films was carded out compared with that of the pure ZnO. The results reveal that, the photoluminescence spectra of bare ZnO film showed a weak bandgap emission at around 378 nm and a broad defect-related emission band centered at 470 nm. After adding Ag film, it resulted in an increase and decrease of the near band edge, meanwhile, the position of UV peak has as lightred-shift compared with that of pure ZnO thin film. The optical features can be influenced by the evolution of the Ag film varied with the deposition time. The reasons for the enhancement of the band edge emission which caused by the surface plasmon resonance coupling of the near band edge emission between Ag and ZnO was detailed discussed.