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. ***
