【摘要】 采用电化学腐蚀的方法制备了不同孔径的多孔硅薄膜样品,并在1050℃高温下进行了退火。采用扫描电镜和拉曼光谱对多孔硅退火前后结构的变化进行了观察,根据晶体形核理论分析了孔径变化的机理,并从热力学角度对其微观机制进行了讨论。实验和理论分析的结果均表明,多孔硅的初始孔径存在一个临界值,初始孔径小于此临界值时,孔在高温退火中有收缩的趋势;反之,初始孔径大于此临界值时,孔有变大的趋势。更多还原

【Abstract】 Porous silicon film samples with different pore sizes were prepared by electrochemical anodization,and then were annealed at 1050℃.The structure of porous silicon before and after annealing was observed by scanning electron microscopy and Raman spectrometry.The mechanism of pore size changes were analyzed according to nucleation theory,and its microscopic mechanism were discussed from the thermodynamic point of view.Experimental and theoretical results confirmed the existence of a critical radius above which the pore size increases and below which the pore size decreases during high temperature annealing.更多还原