铜掺杂多孔硅的光致荧光猝灭  

Quenching of Copper-doped Porous Silicon Photoluminescence

作　　者：李媛媛[1] 李清山[1] 倪梦莹[1] 王会新[1] 曹小龙[1] 

机构地区：[1]曲阜师范大学物理系,山东曲阜273165

出　　处：《发光学报》2004年第5期556-560,共5页Chinese Journal of Luminescence

基　　金：山东省自然科学基金资助项目(Y2002A09)

摘　　要：采用浸泡镀敷的方法在多孔硅表面形成了一铜镀层,通过对掺铜前后多孔硅的光致发光(PL)谱和傅里叶变换红外(FTIR)吸收光谱的研究,讨论了铜在多孔硅表面的吸附对其光致发光的影响。实验表明,掺铜对多孔硅的光致发光具有明显的猝灭效应,并使多孔硅的发光峰位蓝移。由于多孔硅表面铜的吸附使硅 氢键明显减少,而铜原子和硅的悬挂键成键会形成新的非辐射复合中心,从而使多孔硅的光致发光强度衰减。且浸泡溶液的浓度越高,这种猝灭效应越明显。而多孔硅发光峰位的蓝移,则是由于在发生金属淀积的同时伴随着多孔硅表面Si的氧化过程(纳米Si氧化为SiO2)的缘故。The observation of visible photoluminescence (PL) from porous silicon (PS) at room-temperature has stimulated many studies for potential applications in silicon-based optoelectronics. And the PL characteristics of PS is one of the most concentric problems. But the PL mechanism is still a controversial issue. In order to have a further study on the PL characteristics of PS luminescence and discuss the PL mechanism, this letter reported the optical properties of transition-metal (copper) doped porous silicon by immersion plating in metal ion solutions (CuSO_4). Immersion or electroless plating refers to the plating of soluble metal ions onto a base material without applying a bias. In order to research the influence on photoluminescence of PS by copper-doping, the photoluminescence spectrum and the Fourier transform infrared (FTIR) spectroscopy were measured. Comparing the PL spectrum of the as-deposited porous silicon with the Cu-doped PS ,the PL intensity of the Cu-doped PS decreased dramatically and the PL peak locations had a blue shift obviously. That is to say, there was a photoluminescence quenching of porous silicon by immersion plating in copper sulfate solution. And the PL intensity decayed more dramatically with the increasing concentration of the copper sulfate aqueous solution and the immersion time. Fourier transform infrared spectroscopy indicated that: (1) the intensity of the SiH_x stretching absorption peaks (2 090～2 050 cm^(-1)) and the (Si)(H )stretching absorption peaks (620 cm^(-1)) decreased after immersion plating; (2) There was a strong absorption at 1 109 cm^(-1) due to (Si)(O)(Si) in the Cu-doped samples. Studies revealed that the quenching effect of Cu-doped PS may be related to the decrease of (Si)(H) bonding and the nonradiative recombination center played by Cu induced surface electronic states. But the blue shift of the PL peak locations may results from the existence of oxidation on the surface of Cu-doped porous silicon. All of above experiments indicated that, the PL o

关 键 词：多孔硅 光致发光 傅里叶变换红外 浸泡镀敷 猝灭 

分 类 号：O482.31[理学—固体物理]