多孔化PECVD硅薄膜的室温光致发光

Room Temperature Visible PL from Porous PECVD Silicon Film

本文采用阳极氧化腐蚀技术对等离子ＣＶＤ方法制备的微晶硅薄膜进行了多孔化处理．在室温下用Ｎ２激光激发，在多孔化微晶硅薄膜上观测到了强的可见荧光，其荧光谱中包含１．９４ｅＶ和２．８６ｅＶ两个峰．我们还对其激发谱进行了研究，发现除与跃迁有关的吸收峰（３．４ｅＶ）外，在２—３ｅＶ间还有新的吸收峰．此结果与Ｆ．Ｂｕｄａ等人最近对硅量子线的理论计算相符合．

Abstract Our work concenlrates on porous psicrocrystalline silicon films. The Boron-doped hydrogenated microcrystalline silicon films were anodized in hydrofluoric acid solution. The photoluminescence (PL) spectrum and PL excitation spectrum were measured, and the results obtained were compared to thats of porous silicon made from P-type crystalline silicon. The PL spectrum shows two peaks at 2.86eV and 1 .94eV, respectively. The PL excitation spectrum consists of a series of peaks,including three high energy peaks located at 5.16eV, 4.13eV and 3.34eV, respectively, and a low energy peak at 2.9 geV. In conjuction with the absorption spectrum of single ccrystalline silicon, the three high energy peaks should be attributed to the bulklike transitions between r, respectively,while the low energy peak may be a quantum wire-related feature as indicated by F. Buda et al. in the First-Principles electronic structure calculation of Si quantum wires recently.