光化学氧化对多孔硅稳定性及SO_2传感性能影响  

Effect of Photochemical Oxidization on Stability and SO_2 Sensing Performance of Porous Silicon

作　　者：黎学明[1] 王力春[1] 杨建春[2] 

机构地区：[1]重庆大学化学化工学院,重庆400044 [2]教育部光电技术及系统重点实验室

出　　处：《应用化学》2007年第5期512-516,共5页Chinese Journal of Applied Chemistry

基　　金：国家自然科学基金(20007006)资助项目

摘　　要：采用光化学氧化方法对多孔硅进行后处理,获得具有良好稳定性的氧化多孔硅;采用SEM、AFM、FT-IR进行表征;通过SO2传感实验,评价其光致发光谱的变化。结果表明,采用电化学阳极氧化制备的新鲜多孔硅在空气中稳定性较差,SEM图表明其膜层分布有120×40μm的长方形小块,光化学氧化后使该长方形小块进一步分裂变细;AFM图表明,新鲜制备的多孔硅经稳定化处理后,表面硅柱宽度由700～750 nm变为300～350 nm,高度由50～58 nm变为40 nm;出现Si—O键(1 114 cm-1)和OSi—H键(2 249 cm-1)的振动峰;该氧化多孔硅在SO2介质中呈可逆的荧光猝灭特征,荧光峰的位置不随SO2浓度变化而发生移动,稳定性较好。Lightly oxidized porous silicon was prepared by anodizing p-type single crystal silicon and photochemically oxidizing porous silicon. By means of SEM, AFM, FT-IR, the structure and morphology of the porous silicon was analyzed. The sensing performance was studied quantitatively by photoluminescence quenching of porous silicon. The results showed the structure of freshly etched porous silicon was very unstable because the silicon hydride （Si--Hx ） on the porous silicon surface reacted with the ambient air easily. SEM images showed that the surface of the fresh porous silicon was covered by a lot of 120 × 40 μm rectangle pieces. After being oxidized by photochemical method, these rectangle pieces beceme smaller. AFM images indicated the porous silicon was covered by some porous silicon columns, and after being oxidized by photochemical method, the height of the columns decreased from 700 - 750 nm to 300 - 350 nm, and the thickness of the porous film was cut down from 50 -58 nm to 40 nm; and partial Si--Hx band was replaced by Si--O band at around 1 114 cm^-1 and OSi--H band at around 2 249 cm^-1. The sensing experiment showed the photoluminescence of the stabilized porous silicon could be reversibly quenched by sulfur dioxide of different concentrations of, and the corresponding peak wavelength was not changed.

关 键 词：SO2 多孔硅 光致发光 

分 类 号：O644.1[理学—物理化学]