发光多孔硅表面微结构及其晶格畸变的实验研究

用电化学方法制备了不发光多孔硅和发光多孔硅,用X射线双晶衍射对两类多孔硅表面进行了微结构分析和晶体质量表征,实验表明两类多孔硅的微结构间存在着很大差别。不发光多孔硅表面对X射线的双晶衍射摇摆曲线可解叠成两个峰,它们分别来自样品多孔层和单晶硅衬底,而发光多孔硅对X射线的双晶衍射摇摆曲线呈高斯对称分布,不可解叠。发光多孔硅比不发光多孔硅表面晶体质量差,且电化学腐蚀越严重,表面晶体质量下降也越严重。

MICROSTRUCTURE AND LATTICE DISTORTION OF EFFICIENT VISIBLE LIGHT-EMITTING POROUS SILICON

Two kinds of porous sdicon(visible light emitting porous silicon,nonluminous poroussilicon) are fabricated using the anodization method.The microstructure of the porous silicon samplesis studied using X-ray double diffraction technique,and the silicon crystal of the porous silicon samplesis also characterized.The experiments suggest that the microstructure of the visible light-emittingporous silicon is different from that of the nonluminous porous silicon.The silicon crystal perfection ofthe visible emitting porous silicon is worse than that of the nonluminous porous silicon.The greaterthe anodization is carried out,the worse the silicon crystal perfection is.The double crystal rockingcurve of nonluminous porous silicon can be dissociated into two distinct diffraction peaks:One from thesubstrate,the other from the porous layer at a slightly smaller Bragg angle.But the double crystalrocking curves of the visible light-emitting porous silicon samples are symmetrical Gauss distribution.They can't be dissociated.