采用纳米球刻蚀(nanosphere lithography)技术,以自组装的聚苯乙烯纳米小球(polystyrene,PS小球)的单层膜为掩模,制备出二维有序的CdS纳米阵列.利用扫描电子显微镜(SEM)对样品结构进行了表征,用紫外—可见分光光度计对样品光学性质进行了分析.结果表明:制备的二维CdS纳米阵列是高度有序的,且与作为掩模的纳米小球的原始尺寸及排布结构一致;禁带宽度为2.60eV,相对于体材料的2.42eV,向短波长蓝移了0.18eV,表现出CdS材料在纳米结构点阵中的量子尺寸效应;CdS纳米阵列在长波段透光性较好,短波段透光性几乎为零,表现出良好的光透选择性.
We realized the fabrication of 2D ordered arrays of CdS nanocrystals by nanosphere lithography by use of a monolayer of self-assembled polystyrene spheres 220 nm in diameter as a mask. We used scanning electron microscope (SEM) to characterize the structure of samples. The results indicate that the 2D arrays of CdS nanocrystals produced by nanosphere lithography have highly ordered structure which has the same period of the original PS mask. According to the transmission spectrum, it is estimated that the forbidden band width of the CdS nanocrystals is around 2.60 eV, which shows a size-dependence of the CdS nanocrystals. This structure has the promising application in the light filter and single-photon emitter.