ZnS films are grown at 250 ℃ and 350℃ by pulsed laser deposition (PLD) on porous silicon (PS) substrates which are prepared by electrochemical anodization. X-ray diffraction (XRD) patterns show that ZnS films are grown in preferred orientation along -ZnS (111) direction. With higher growth temperature, the diffraction peak intensity of ZnS films is larger. Scanning electron microscope (SEM) images indicate that the surface of ZnS films grown at 250 ℃ is loose and unsmoothed which is attributed to the rough structure of PS substrate while the film surface becomes smooth and compact at 350 ℃ although some crystalline grains with apparent size appears. The photoluminescence (PL) spectra is measured at room temperature, the result shows that the self-activated luminescence of ZnS films grown at 350 ℃ is larger than that of 250℃, while the red light intensity of PS is lower than that of 250 ℃ along with the redshift of the peak position. Combining the blue, green emission from ZnS with the red emission from PS, a broad PL band in the visible region from 450 nm to 700 nm is obtained, and the ZnS/PS composites exhibit intense white light emission.%在电化学阳极氧化法制备的多孔硅(porous silicon,PS)衬底上用脉冲激光沉积法(pulsed laser deposition,PLD)在250℃和350℃下生长ZnS薄膜。XRD图样显示,制备的ZnS薄膜沿β—ZnS(111)方向择优生长,较高的生长温度下,衍射峰强度较大。SEM结果表明,250℃生长的ZnS溥膜表面疏松、不平整,这是由于衬底PS的粗糙结构所致,而350℃生长温度下,尽管薄膜表面出现了一些明显尺寸的晶粒,但总体变得平整致密。室温下的此致发光(PL)谱表明,350℃样品中ZnS的自激活发光强度高于250℃样品,而PS的红光强度低于250℃样品且峰位红移。把ZnS的蓝绿光与PS的红光叠加,在可见光区450~700nm形成了一个较宽的光致发光谱带,ZnS/PS复合体系早现较强的白光发射。
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