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用常规电化学方法制备了发射高效可见光的多孔硅样品。对样品进行了光谱研究。用非化学方法从样品表面得到了粉末状荧光物质(非多孔硅膜研磨产物),光谱测定证实它的光致发光光谱与原多孔硅样品光致发光光谱相同,粉末进一步研磨后仍能发出同样的可见光。多孔硅样品还可以实现阴极射线激发发出同样的高效可见光,但易因电子束的轰击而发光强度较快减弱。用扫描电镜(SEM)对多孔硅样品的形貌、结构、荧光粉末的形状、尺寸、多孔硅样品阴极荧光发射区域进行了系统的研究。实验结果表明多孔硅样品一般可分为三层结构:表面层、多孔层和单晶硅衬底,样品荧光是来源于其表面层的。对样品表层组分的x射线光电子谱(XPS)分析表明,此时的多孔硅表层有大量非硅元素存在,如:C、O、F(没考虑H),硅元素的原子个数比只占30％～50％。用同样的电化学方法在单晶硅未抛光面上和多晶硅未抛光面上制得了均匀发射可见光样品。上述实验结果说明,多孔硅的高效可见光发射是来源于样品制备过程中在其表面层中形成的粉末状荧光物质。
Porous silicon samples emitting high-efficiency visible light were prepared by conventional electrochemical methods. The samples were subjected to spectroscopic studies. A non-chemical method was used to obtain a powdery fluorescent substance (non-porous silicon film ground product) from the surface of the sample. The spectroscopic measurement confirmed that its photoluminescence spectrum was the same as the photoluminescence spectrum of the original porous silicon sample. The powder could still emit the same after further grinding Visible light. Porous silicon samples can also achieve the same high-efficiency visible light emitted by the cathode ray, but easily weakened due to the electron beam bombardment. The morphology and structure of porous silicon samples, the shape and size of fluorescent powders, and the cathodal fluorescence emission of porous silicon samples were systematically investigated by scanning electron microscopy (SEM). Experimental results show that porous silicon samples can be generally divided into three layers: the surface layer, porous layer and single crystal silicon substrate, sample fluorescence is derived from the surface layer. X-ray photoelectron spectroscopy (XPS) analysis of the surface components of the sample showed that there were a large number of non-silicon elements in the porous silicon surface at this time, such as C, O and F (without considering H), the atomic number ratio of silicon Accounting for 30% to 50%. The same electrochemical method was used to produce uniform emission of visible light samples on uncoated single-crystal silicon and unpolished polycrystalline silicon. The above experimental results show that the efficient visible light emission of porous silicon is derived from the powdered fluorescent substance formed in the surface layer during sample preparation.