AVS 46th International Symposium
    Surface Science Division Wednesday Sessions
       Session SS3+NS-WeA

Paper SS3+NS-WeA9
Spontaneous Island Formation on the GaAs(001) 2x4 Reconstructed Surface

Wednesday, October 27, 1999, 4:40 pm, Room 604

Session: Islands, Clusters, and Steps
Presenter: P.M. Thibado, University of Arkansas
Authors: P.M. Thibado, University of Arkansas
V.P. LaBella, University of Arkansas
M. Anser, University of Arkansas
Z. Ding, University of Arkansas
D.W. Bullock, University of Arkansas
Correspondent: Click to Email
Given the growing use of III-V semiconductor materials in wireless and high speed communication devices the preparation of atomically flat single crystal GaAs(001) surfaces was examined, since these devices are primarily fabricated using epitaxial methods . To achieve this, a state of the art molecular beam epitaxy (MBE) system with a novel temperature measurement system accurate to within ±2 @super o@C, has been combined, in situ, with a scanning tunneling microscope (STM). Surprisingly, when the GaAs( 001) 2x4 reconstructed surface is annealed above a critical temperature (570 @super o@C), under a constant As@sub 4@ flux, it spontaneously forms one monolayer high islands covering one half of the otherwise flat terraces. This process is reversible and when fit to a free energy model yields information about the surface bonding energies. This work was funded in part by the National Science Foundation (DMR-9733994) and the Office of Naval Research (N00014-97-1-1058).