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在４８８ｎｍ 的Ａｒ＋ 激光激发下，Ｓｉ覆盖的部分氧化多孔硅（ＰＯＰＳ）的光致发光谱（ＰＬ）在１．７８ｅＶ 处展示了一个稳定的ＰＬ峰，它的强度达到刚制备多孔硅的发光强度．使用Ｘ 射线衍射、Ｒａｍ ａｎ 散射、傅里叶变换红外吸收和电子自旋共振等对其发光机理进行了系统的研究．结果表明，这个增强的ＰＬ峰不是起源于量子限制硅晶粒中的带带复合，也不是起源于样品表面局域态或硅晶粒与氧化物之间的界面态的辐射复合．通过与Ｇｅ覆盖的部分氧化多孔硅的相关结果比较，我们认为这个稳定增强的ＰＬ峰起源于氧相关缺陷中心的光学跃迁
The photoluminescence spectrum (PL) of Si-covered partially oxidized porous silicon (POPS) shows a stable PL peak at 1.78 eV with Ar + laser excitation at 488 nm and its intensity reaches the luminescence intensity of freshly prepared porous silicon . The mechanism of its luminescence has been studied systematically using X-ray diffraction, Ram an scattering, Fourier transform infrared absorption and electron spin resonance. The results show that this enhanced PL peak does not originate from the band recombination in the quantum confined silicon grains nor from the radiative recombination that originates from the surface states of the sample surface or the interfacial state between the silicon grains and the oxide. We consider this steadily enhanced PL peak to originate from the optical transition at the center of oxygen-related defects by comparison with the results of Ge-covered partially oxidized porous silicon