Interface Formation with Atoms, Ions, and Clusters

原子、离子和团簇的界面形成

• 批准号: 9216178
• 负责人: James Chelikowsky
• 金额: $ 30.05万
• 依托单位: University of Minnesota-Twin Cities
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-04-01 至 1997-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9216178&HistoricalAwards=false
• 关键词: Interface; Formation; Atoms; Ions; Clusters

The goal of this research is to explore interfacial phenomena associated with the deposition of atoms, ions, and clusters on semiconductor surfaces. This work combines scanning tunneling microscopy with ab initio molecular dynamics simulations to correlate interfacial structures and properties with the dynamics of condensation ions and small clusters are deposited directly on the substrate using laser-assisted supersonic expansion. The experimental studies are unique because the energy, the trajectory, and the number of atoms in the cluster are controlled and because scanning tunneling microscopy is used to image the resultant surface and overlayer structure. The theoretical studies are unique because new computational techniques are implemented for determining the structure and interaction parameters of atoms and clusters on surfaces. These studies should allow analysis of growth conditions with quantum interatomic forces and testing of the predictions with surface analysis techniques. The proposed studies are important because the focus on properties of complex non-equilibrium systems where chemical and physical properties at the interface change over microscopic scales. Interface formation during non-equilibrium vacuum deposition is one of the challenging problems in the present day solid state sciences. Because the goal of this research is to correlate interface properties and interface structure, the successful realization of the proposed work will have significant impacts on the nano-fabrication of new electronic devices and the understanding of other surface related processes such as catalysis.

这项研究的目标是探索与半导体表面上原子、离子和团簇沉积相关的界面现象。这项工作将扫描隧道显微镜和从头算分子动力学模拟相结合，将界面结构和性质与凝聚离子的动力学相关联，并利用激光辅助超声膨胀直接在衬底上沉积小团簇。实验研究是独一无二的，因为团簇中的能量、轨迹和原子数量是可控的，而且扫描隧道显微镜被用来成像得到的表面和覆盖层结构。理论研究是独一无二的，因为采用了新的计算技术来确定表面原子和团簇的结构和相互作用参数。这些研究应该可以用量子原子间作用力来分析生长条件，并用表面分析技术来检验预测。提出的研究很重要，因为它关注的是复杂的非平衡系统的性质，其中界面的化学和物理性质在微观尺度上发生变化。非平衡真空沉积过程中的界面形成是当今固体科学中具有挑战性的问题之一。由于本研究的目标是将界面性质和界面结构关联起来，因此这项工作的成功实现将对新型电子器件的纳米制造以及对催化等其他表面相关过程的理解产生重大影响。