稀土钇掺杂多孔硅光致发光研究

Study on photoluminescence of porous silicon doped with rare earth element yttrium

采用电化学方法在多孔硅中掺杂了稀土钇(Y)元素。用荧光分光光度计分析了样品的光致发光特性。多孔硅样品在440nm波长激发下,光致发光谱上主发光峰位于620nm,认为其来源于Si-O复合物的发光中心;多孔硅样品在390nm波长激发下,光致发光谱上主发光峰分别位于527和576nm,并且用量子限制/发光中心模型加以解释。钇掺杂多孔硅样品的光致发光强度明显增强,并且在484nm附近出现新的发光峰。分析结果认为,这是由于钇的掺入,在多孔硅禁带中形成了新的表面能级,从而形成新的发光中心的结果。

The rare earth element yttrium （Y） was doped in porous silicon with electrochemical method . The photoluminescence （PL） properties of the samples were studied with fluorescence spectrophotometer. Under excitation by laser with wavelength of 440nm, porous silicon has its photoluminescence peak located at 620nm, which is considered come from luminescence center of Si-O complex; under excitation by laser with wavelength of 390nm, porous silicon has photoluminescence peak located at 527nm and 576nm, with an explanation by QCLC model. Photoluminescence of yttrium-doped porous silicon get an obvious enhancement, with a new peak located around 484nm. Analysis reveals that this is resulted from doping of yttrium, which forms new surface energy levels in band gap of porous silicon, consequently forms new luminescence centers.