电流密度对光电化学腐蚀宏孔硅阵列形貌的影响

宏孔硅阵列(MSA)在光子晶体、硅微通道板、MEMS 器件等领域应用前景广阔,引起人们广泛关注。为制备理想的MSA结构,本文开展了MSA光电化学方法腐蚀实验,重点研究了腐蚀电流密度对宏孔形貌的影响。给出了n型硅抛光片背面光照情况下在氢氟酸溶液中的电流-电压扫描曲线,讨论了临界电流密度JPS的意义和MSA稳定生长的基本电流密度条件。提出了一种间接地测量JPS与腐蚀时间关系的方法,并根据JPS的测量结果调整腐蚀电流,实现了理想的MSA等径生长,制备出孔深度为295m,长径比为98的MSA结构。     

便携式CCD尺寸检测技术研究

便携式尺寸检测系统具有非接触、使用灵活的特点,可以应用于环境复杂、仪器不易摆放的场所,本文介绍了便携式尺寸检测系统工作原理,并对影响测量精度的光学系统几何畸变、距离信息采集、曝光时间等各种因素进行了分析,尤其针对便携式系统提出了手动扫描极小值采集测量方案,提高了系统的检测精度.     

Influence of voltage on photo-electrochemical etching of n-type macroporous silicon arrays

The influence of voltage on photo-electrochemical etching(PEC) of macroporous silicon arrays(MSA) was researched.According to the theory of the space charge region,I-V scan curves and the reaction mechanism of the n-type silicon anodic oxidation in HF solution under different current densities,the pore morphology influenced by the working voltage were studied and analyzed in detail.The results show that increasing the etching voltage will lead to distortion of the pore morphology,decreasing etching volta...     

离轴倾角磁控溅射生长氧化锌薄膜及其物性研究

宽禁带半导体ZnO具有高激子束缚能(60MeV)、低生长温度和低成本等诸多优势,是一种理想的紫外光电材料.作为光电器件的核心部分,薄膜质量是影响器件性能和表现的关键.因此,高质量ZnO薄膜的制备具有重要研究意义.相比于分子束外延和金属有机化学气相沉积等薄膜生长方法,磁控溅射技术具有明显的成本优势,并且适于大尺寸薄膜的生长,是薄膜生长工业中利用率最高的一种技术手段.采用新型共溅射磁控溅射系统,以离轴倾角溅射方式在硅基片上沉积一系列ZnO薄膜,探究了溅射功率和生长气氛等主要工艺参数对ZnO薄膜的形貌、结构和发光等物性的影响.     

电压对N型宏孔硅阵列光电化学腐蚀的影响

研究了电压对宏孔硅阵列光电化学腐蚀的影响. 根据空间电荷区理论、N型硅片在HF酸溶液中I-V扫描曲线、不同电流密度条件下硅阳极氧化反应机理,系统地分析研究了腐蚀电压对宏孔硅阵列形貌的影响.研究结果表明：电压升高使孔型变差,电压降低则盲孔率提高,腐蚀电压恒定、长时间腐蚀孔将逐渐分叉。根据理论分析,优化了工艺参数,制备出高长径比宏孔硅阵列结构,孔深度为317m,方孔边长为3m,长径比为105。     

Influence of etching current density on the morphology of macroporous silicon arrays by photo-electrochemical etching

Macroporous silicon arrays(MSA) have attracted much attention for their potential applications in photonic crystals,silicon microchannel plates,MEMS devices and so on.In order to fabricate perfect MSA structure,photo-electrochemical (PEC) etching of MSA and the influence of etching current on the pore morphology were studied in detail.The current-voltage curve of a polished n-type silicon wafer was presented in aqueous HF using back-side illumination.The critical current density J_(PS) was discussed and ...     

基于众值理论的微光图像帧积分算法

帧积分算法是图像增强技术中常用的一种方法,它在处理微光图像时有一定的局限性.本文对此做了进一步的实验与讨论,提出了一种改进的算法——众值帧积分.众值帧积分是对邻帧内对应像素点的灰度值作数学统计,并取出现几率最大的像素灰度值作为滤波结果,因此处理过的图像更接近真实.实验结果表明,众值帧积分能有效地抑制微光图像中的亮点噪声和暗点噪声,对图像边缘的保护特性比帧积分好,具有重要实用价值.     

Influence of O/Ar ratio on the properties of NiO thin film grown with the method of radio-frequency magnetron sputtering

In order to obtain high quality NiO thin film grown with the radio-frequency magnetron sputtering method, the influence of O/Ar ratio on the structure, band-gap, resistivity and optical transmittance of NiO thin films were studied. It was found that the obtained NiO thin film showed (111) preferred orientation and higher transparency in the visible region. With the increasing of O/Ar ratio from 1∶7 to 8∶2, the optical transmittance of NiO thin films decreased and the optical band-gap was between 3.4 eV and 3.7 eV, and the sheet resistivity decreased from 5.4×107 Ω/□ to 1.0 ×105 Ω/□. Our study shows that the properties of NiO thin films can be adjusted in a wide range by adjusting the O/Ar ratio in the sputtering process.     

基于EDXRF光谱法的水系沉积物中多种重金属成分分析

采用粉末样品压片制样,用能量色散X射线荧光光谱仪对长春南湖湖底沉积物中Ba、Pb、As、Cr、Co、Ni、Cu、Zn多种元素进行测定。重点研究了元素的测定条件、背景选择和谱线校正问题。经检验,结果符合标准,方法的检出限和精确度能够满足环境检测化探试样的分析要求。用GWB07305水系沉淀物成分分析标准物质进行测试,精密度（RSD）除Cr〈15%外,其余元素均〈9%。结果表明,EDXRF光谱法的精密度和准确度能够满足水系沉积物检测要求。