论文部分内容阅读
采用电化学腐蚀制备多孔硅,利用场致发射扫描式电子显微镜(field emission scanning electron microscope,FESEM)观测多孔硅的二维微观形貌,利用Nano Indenter XP中的纳米轮廓扫描仪组件(nano profilometry,NP)得到其三维拓扑分析图像,分析了微观结构差异的原因并讨论了多孔硅内部微观结构对其机械性能的影响;利用MTSNano Indenter XP纳米压入测量仪器,研究了多孔硅的显微硬度和杨氏模量随压入深度的变化规律,比较了不同孔隙率多孔硅的机械性能差别.实验结果测得40mA/cm2,60mA/cm2,80mA/cm2和100mA/cm2四个不同腐蚀电流密度条件下制备多孔硅样品的孔隙率在60%-80%范围内,孔隙率随着腐蚀电流密度的增加而增大;在氢氟酸(HF)浓度为20%的条件下制备出多孔硅样品的厚度在40μm-50μm范围内;测得多孔硅的平均硬度、平均杨氏模量分别在0.478GPa-1.171GPa和10.912GPa-17.15GPa范围内,并且其数值随腐蚀电流密度的增加而减小,在纳米硬度范围内随压入深度的增加而减小,在显微硬度范围内其数值保持相对恒定,分析了样品表面、厚度、微观结构,及环境对其机械性能的影响,得到了多孔硅力学性能随其微观尺度形貌的变化规律.
The porous silicon was prepared by electrochemical etching. The two-dimensional microstructure of porous silicon was observed by field emission scanning electron microscope (FESEM). The nano-profilometry (Nano Indenter XP) NP) were used to obtain the 3D topological analysis images. The reasons for the differences in microstructure were analyzed and the influence of microstructure on the mechanical properties was discussed. The microstructure and mechanical properties of porous silicon were studied by using MTSNano Indenter XP nano- Young’s modulus changes with the depth of penetration into different porosity porous mechanical properties were compared.The experimental results measured 40mA / cm2, 60mA / cm2, 80mA / cm2 and 100mA / cm2 four different corrosion current density conditions Porous silicon samples prepared under the porosity range of 60% -80%, the porosity increases with the increase of the corrosion current density; prepared at a hydrofluoric (HF) concentration of 20% of the porous silicon samples The average thickness and the average Young’s modulus of the porous silicon were in the range of 0.478GPa-1.171GPa and 10.912GPa-17.15GPa, respectively, and their values were correlated with the corrosion current The density decreases and increases with the depth of the nano-hardness decreases, and its value in the microhardness remains relatively constant, the analysis of the sample surface, thickness, microstructure, and the environment for its mechanical properties The mechanical properties of porous silicon with its microscopic morphology changes.