Kinetics Versus Thermodynamics: A Study of Molecular-Beam Epitaxy Growth of Gallium Arsenide

小行星9802586 这个项目旨在促进对GaAs MBE中动力学和热力学的相对作用的理解。该方法包括实验和理论相结合，研究清洁GaAs表面上的动态过程，如表面移动的Ga吸附原子之间的相互作用和As解吸。实验包括静态退火探测作为解吸和自由Ga动力学，步骤的能量测量条件下的作为或Ga终止，和步骤不稳定性的研究。所获得的数据预计将有助于揭示薄膜生长过程中的动力学过程和平衡热波动之间的相对重要性。 该项目解决了具有高技术相关性的材料科学专题领域的基础研究问题。该研究将在基础层面上为电子/光子器件的重要方面提供基础材料科学知识。 现在已有实验工具，可以在原子水平上观察基本的表面过程，如果能更好地了解这些过程，就可以在基础和技术领域取得进展。从研究中获得的基本知识和理解预计将有助于提高先进器件和电路的性能和稳定性，为设计和生产改进的材料和材料组合提供基本的理解和基础。 该计划的一个重要特点是通过在一个基本和技术上重要的领域对学生进行培训来整合研究和教育。 ***

9802586 Orr This project seeks to advance understanding of the relative role of kinetics and thermodynamics in GaAs MBE. The approach involves a combination of experiment and theory to study dynamic processes on clean GaAs surfaces such as the interactions between surface- mobile Ga adatoms and As desorption. Experiments include static annealing to probe As desorption and free Ga dynamics, step energy measurements under conditions of As or Ga termination, and step instability studies. Data obtained is expected to help reveal the relative importance between kinetic processes and equilibrium thermal fluctuations during film growth. %%% The project addresses basic research issues in a topical area of materials science having high technological relevance. The research will contribute basic materials science knowledge at a fundamental level to important aspects of electronic/photonic devices. Experimental tools are now available to allow atomic level observation of basic surface processes which when better understood will allow advances in both fundamental and technological arenas. The basic knowledge and understanding gained from the research is expected to contribute to improving the performance and stability of advanced devices and circuits by providing a fundamental understanding and a basis for designing and producing improved materials, and materials combinations. An important feature of the program is the integration of research and education through the training of students in a fundamentally and technologically significant area. ***