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Dynamics of spontaneous roughening on the GaAs[001] surface

Devices based on III-V compound semiconductors have fueled the growth of the multi-billion dollar telecommunications industry. Unlike silicon-based devices, which are produced primarily by ion implantation, III-V device structures must be produced by depositing one plane of atoms after another until the entire structure is grown. Necessarily, III-V device fabrication occurs solely at a surface. The better one can control and manipulate the motion of atoms on surfaces, the more sophisticated the device structures one can make. In order to better understand the surface processes important to device fabrication, we have combined, for the first time, three major advances in semiconductor growth and characterization: (1) state-of-the-art semiconductor growth via molecular beam epitaxy (Riber 32P), (2) optical transmission substrate temperature determination via the band gap (0-700/spl deg/C with /spl plusmn/2/spl deg/C accuracy, updated at 1 Hz), and (3) in situ, atomic-resolution surface characterization via scanning tunneling microscopy (Omicron). With these three technological breakthroughs, we have successfully conducted nanoscale experiments on the well-studied GaAs[001]-(2/spl times/4) surface.