多孔硅的微观结构及其氧化特性

Microstructure and Oxidation of Porous Silicon

采用ＴＥＭ技术研究了多孔硅微观结构．结果表明：当衬底材料为中等偏高掺杂（０．０３２Ω·ｃｍ）时，多孔硅具有两种不同类型的微观结构，它们的形成和阳极氧化反应电流密度有关．修正了Ｂｅａｌｅ关于多孔硅微观结构的形成模型．采用ＸＰＳ、ＩＲＳ和击穿电压测量，研究了多孔氧化硅的特性，发现多孔硅在低温下（７５０℃）的氧化特性，除了和多孔度有关外，和多孔硅的微观结构以及氧化前的热处理温度有关．

Abstract The microstructure of porous silicon is studied by using cross-section transmission electron microscopy technique. The results show that in the substrate doping level a bit heavier than moderate concentration (0. 032 Ω· cm), the formation of two distinct types of microstructure of porous silicon depends on anodization current density. In this work,Beale's model on the formation of microstructure of porous silicon is modified. The properties of porous oxidized silicon are inverstigated by XPS, IRS and breakdown measurement,which indicate that oxidation properties of porous silicon under low temperature (￣750℃)is related not only to the porosity of porous silicon but also the microstructure, as well as the temperature of heat treatment of porous silicon before oxidation.