Study of Growth/Etch Front Roughening at Far-From-Equilibrium

在非平衡条件下，表面蚀刻/生长过程中界面粗糙度的形成不能用传统的统计力学来描述。动态标度假设与模拟和连续介质理论相结合的最新发展为非平衡物理研究指明了一个令人兴奋的新方向。许多实验系统将用于定量地探索远离平衡的粗化现象，并设计用于测试动态标度假设。该系统包括表面的蚀刻（等离子蚀刻、离子溅射和反应性离子蚀刻）和表面上薄膜（包括聚合物）的生长。最先进的技术将用于跨越垂直（界面宽度）和水平（横向相关）方向的宽长度尺度，以实时测量界面粗糙度。粗糙度和形貌将采用噪声诱导和其他生长机制，包括侧壁生长和各向异性生长进行模拟。从实验和模拟中测量的粗糙度指数和界面生长指数将用于建立动态结垢现象的通用性类。预计对生长/蚀刻前沿粗化现象的基本理解加上实时监测表面的表征技术将允许在实际应用中控制界面粗糙度。界面粗糙度是薄膜和器件加工中的核心问题之一，它直接控制着薄膜和器件的许多物理和化学性能。本研究探讨了在远离平衡条件下表面生长/蚀刻过程中形成界面粗糙度的基本方面。在蚀刻领域，半导体加工技术，如等离子体蚀刻、离子溅射和反应离子蚀刻将被使用。研究气相沉积法生长聚合物薄膜的形态和演化，将在生长领域掀起新的浪潮。学生将利用原子力显微镜、光散射、x射线衍射和电子衍射来测量和量化界面粗糙度。采用分形维数的动态标度理论对随时间变化的粗糙度数据进行分析。在这个研究项目中训练的学生将顺利过渡到学术或工业环境

9971265Wang The formation of interface roughness during the etching/growth of surfaces under far-from-equilibrium conditions cannot be described by conventional statistical mechanics. Recent development of the dynamic scaling hypothesis coupled with simulations and continuum theory point to an exciting and new direction in the area of non-equilibrium physics research. A number of experimental systems will be used to explore quantitatively the roughening phenomena at far-from-equilibrium and are designed to test the dynamic scaling hypothesis. The systems include etching of surfaces (plasma etching, ion sputtering, and reactive ion etching) and growth of films (including polymers) on surfaces. State-of-the-art techniques will be used to span a wide length scale both in the vertical (interface width) and horizontal (lateral correlation) directions to measure the interface roughness in real-time. The roughness and morphology will be simulated using noise-induced and other growth mechanisms including sidewall growth and anisotropy growth. The roughness exponent and interface growth exponent measured from experiments and simulations will be used to establish the universality class of dynamic scaling phenomenon. It is anticipated that a fundamental understanding of the growth/etch front roughening phenomena coupled with characterization techniques to monitor the surface in real-time will allow the control of interface roughness in practical applications.%%%Interface roughness is one of the central issues in thin film and device processing and it directly controls many physical and chemical properties of films and devices. This research investigates fundamental aspects of the formation of interface roughness during growth/etching of surfaces under far-from-equilibrium conditions. In the etching area, semiconductor-processing techniques such as plasma etching, ion sputtering, and reactive ion etching will be used. A new effort in the growth area will be initiated to study the morphology and evolution of polymer film growth by vapor deposition. Students will utilize atomic force microscopy, light scattering, x-ray diffraction and electron diffraction to measure and quantify the interface roughness. The time dependent roughness data will be analyzed using dynamical scaling theories with fractal dimensions. Students trained under this research program will have a smooth transition to either an academic or an industrial environment.***