Electrochemistry and Structures of Silicon Surface

从原子水平到微米尺寸,准确控制硅表面结构的精密加工,诸如无序的表面粗糙或者精细的图案,乃是电子元件性能及其可靠性的保证.硅在液中的湿清洗以及硅表面侵刻的电化学反应对硅表面结构的形成具有重要作用.近数十年来,有关阐明和控制硅/溶液界面上复杂的电化学反应及其与表面结构形成的关系已有大量的研究,相关研究成果已在新近编著成书.本文综合有关方面研究资料评述现代硅溶解及其形成的表面结构.Accurate control and fabrication of silicon surface structures from atomic scale to micrometer scale,which may be randomly associated with surface roughness or have well defined patterns,is critical for the per-formance and reliability of electronic devices.Electrochemical reactions of silicon in solutions involved in wetcleaning and etching of silicon wafer play an importantrole in determining the structures of silicon surface.Atre-mendous amount of researches have been done in the last several decades to understand and control a range ofcomplex electrochemical reactions at silicon/solution interface and their relations to the resulted surface struc-tures.The findings generated from these research efforts have been compiled and integrated in a recently pub-lished book.This paper is to present an overview,using synthesized information from this book,on the aspect ofsilicon dissolution and the resulted surface structures.作者联系地址：加拿大安大略Teck comino金属有限公司 厦门大学化学系,,福建厦门361005Author's Address: Teck Cominco Metals Ltd,Ontario,Canada;Department ofChemistry,Xiaman University,Xiaman,Fujian,Chin

Electrochemical Behavior of Zinc-Bismuth Alloy Electrodes in Gelled Electrolytes

锌电极的自腐蚀速率,持续放电下的阳极溶解速率和电极钝化的难易程度是碱性电池性能的重要电化学参数.本文应用线性极化、恒流放电等电化学实验方法研究了电解液中添加CArbOPOl树脂以及电极中添加bI对锌电极电化学行为的影响.并应用金相显微镜和环境扫描电子显微镜(ESEM)对锌电极和锌铋合金电极浸蚀及放电后的形貌进行了表征.结果表明:电解液中添加适量的CArbOPOl树脂可明显提高电极的极化电阻,显著降低电极的自腐蚀速率;阳极的溶解电位出现不同程度的正移,阳极过电位显著增大且大电流密度放电时较明显促进电极钝化.锌电极中添加一定量的bI对改善电极表面氧化物膜的沉积形貌和电极表面固液界面的传质条件,减小电极的自腐蚀速率,抑制电极自腐蚀等方面具有显著作用.The self-corrosion rate, anodic dissolution rate, and passivating tendency of a zinc anode are important parameters that affect the performance of alkaline batteries.Effects of the addition of Carbopol resin to the electrolyte and the addition of passivation Bi passivation to the electrodes on the electrochemical behavior of Zn electrodes were investigated by linear polarization and chronopotentiometry.Surface morphologies of Zn electrodes and Zn-Bi alloy electrodes after etched and constant current dissolution were examined using a metallographic microscope and environmental scanning electron microscope (ESEM).Results showed that the addition of Carbopol resin significantly enhanced the polarization resistance, decreased the self-corrosion current, led to a positive shift in anodic dissolution potential, remarkably increased the anodic overpotential and promoted the passivation of alloy electrodes.The addition of Bi markedly improved the oxide film morphology and mass transfer between solid-liquid interfaces, decreased the self-corrosion rate of Zn electrodes and inhibited the self-corrosion process in Zn electrodes.国家自然科学基金(50731004);国家科技支撑计划(2007BAB27B04-N43CTT)资助项目---

Electrochemical Behavior of Zinc-Bismuth Alloy Electrodes in Gelled Electrolytes

The self-corrosion rate, anodic dissolution rate, and passivating tendency of a zinc anode are important parameters that affect the performance of alkaline batteries. Effects of the addition of Carbopol resin to the electrolyte and the addition of passivation Bi passivation to the electrodes on the electrochemical behavior of Zn electrodes were investigated by linear polarization and chronopotentiometry. Surface morphologies of Zn electrodes and Zn-Bi alloy electrodes after etched and constant current dissolution were examined using a metallographic microscope and environmental scanning electron microscope (ESEM). Results showed that the addition of Carbopol resin significantly enhanced the polarization resistance, decreased the self-corrosion current, led to a positive shift in anodic dissolution potential, remarkably increased the anodic overpotential and promoted the passivation of alloy electrodes. The addition of Bi markedly improved the oxide film morphology and mass transfer between solid-liquid interfaces, decreased the self-corrosion rate of Zn electrodes and inhibited the self-corrosion process in Zn electrodes.National Natural Science Foundation of China [50731004]; National Sci-Tech Supporting Program of China [2007BAB27B04-N43CTT

Electrochemical Behavor of Zinc-Indium Alloy Electrodes in Concentrated Alkaline Solution

应用动电位扫描,恒流放电等电化学方法研究含铟锌电极的电化学行为.用SEM和EDS观察放电后的Zn-In合金电极表面形貌,初步探讨了不同In含量的锌-铟合金电极在浓KOH溶液中电化学行为及其影响因素.结果表明,与纯锌电极相比,Zn-In合金的电极致钝电流增大,达到钝化的时间缩短,从而明显地提高了该电极的电化学活性.The electrochemical behavior of zinc-indium alloy electrodes in 35%KOH solutions has been investigated by electrochemical methods including the potentiodynamic polarization and discharge measurements under constant current density.The results indicate that the anodic current density and passive current density increase after the indium addition.The discharge measurement shows that the addition of indium shortens the time to passive state for the Zn alloy compared to pure zinc at a large discharge conditions,that is the addition of indium may enhance the electrochemical activity of Zn alloy electrodes.It is found that the anodic dissolution of zinc-indium alloy electrodes in the concentrated KOH solution occurs along the certain crystalline face,and the surface roughness increases with the increasing of indium addition due to the anodic dissolution.作者联系地址：厦门大学化学化工学院化学系固体表面物理化学国家重点实验室,加拿大Teck Cominco金属公司,厦门大学化学化工学院化学系固体表面物理化学国家重点实验室,厦门大学化学化工学院化学系固体表面物理化学国家重点实验室 福建厦门361005,L5K1B4加拿大,福建厦门361005,福建厦门361005Author's Address: 1.State Key Laboratory of Physical Chemistry of Solid Surfaces,Department of Chemistry,Xiamen University,Xiamen 361005,Fujian,China,2.Teck Cominco Metals Ltd,Canad