The Chemistry of Etching: Understanding Kinetic Surface Morphologies on an Atomic Scale

该研究项目由分析和表面化学项目支持，研究硅表面蚀刻的机理。利用扫描探针显微镜和动力学蒙特卡罗模拟方法的结合，康奈尔大学化学系的Hines教授和她的同事正在研究蚀刻条件对硅表面形貌的影响。实验解决了KOH溶液对Si（111）表面的水蚀刻，以及用于制造多孔硅材料的硅表面的阳极蚀刻。考察了台阶取向、台阶密度、硅掺杂剂以及蚀刻剂的组成和浓度等因素的影响。这项工作的结果对于纳米材料技术的设计以及电子材料加工策略的发展具有重要意义。关于化学蚀刻剂如何从硅片表面去除材料的信息对于制造微机电（MEMS）器件的工艺设计以及电子和光子器件的生产非常重要。本研究项目的工作旨在发展对硅的水性和电化学蚀刻的理解，目标是发展对蚀刻表面的原子和纳米尺度形态控制的微观理解。在分析和表面化学项目的支持下，Hines教授和她在康奈尔大学的同事们正在使用显微镜和计算机模拟相结合的方法来获得这些信息。

This research project, supported in the Analytical and Surface Chemistry Program, addresses the mechanism of etching of silicon surfaces. Using a combination of scanning probe microscopy and kinetic Monte Carlo simulation methods, Professor Hines and her colleagues in the Department of Chemistry at Cornell University are investigating the effect of etching conditions on the silicon surface morphology. Experiments are addressing the aqueous etching of the Si(111) surface by KOH solution, as well as the anodic etching of silicon surfaces used to create porous silicon materials. The effects of step orientation, step density, and silicon dopant, as well as etchant composition and concentration are being examined. Results of this work are important for the design of nanomaterial technologies, as well as for the development of electronic materials processing strategies. Information about how chemical etchants remove material from the surface of a silicon wafer is important for the design of processes to make micro-electromechanical (MEMS) devices, and for the production of electronic and photonic devices. The work of this research project is directed to developing an understanding of the aqueous and electrochemical etching of silicon, with the goal of developing a microscopic understanding of what controls the atomic and nano-scale morphology of the etched surface. With the support of the Analytical and Surface Chemistry Program, Professor Hines and her colleagues at Cornell, are using a combination of microscopy and computer simulation to obtain this information.