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Although much of the detail of the surface kinetic processes and rates during molecular beam epitaxial growth of compound semiconductors remains uninvestigated, computer simulations employing parameterised rates have nethertheless begun to reveal the significance of the interplay of the surface kinetic processes to the growth mechanism and the resulting atomistic nature of interfaces. The presence of the dissociative surface chemical reaction kinetics of the group V molecular species, in addition to the surface migration and desorption kinetics accounted for in historical atomistic models and simulations of crystal growth, is revealed in the work of Ghaisas and Madhukar to lead to a configuration-dependent-reactive-incorporation (CDRI) growth process. Its limiting cases -the Reaction Limited Incorporation (RLI) and Configuration Limited Reactive Incorporation (CLRI) growth mechanisms - are shown to have significant consequences for the time dependent morphology of the growing surface revealed in the behavior of the average terrace width (<W>) and mean square fluctuations in step height (σh). Consequences of these features as a function of the kinetics of growth have been calculated for the behavior of the reflection-high-energy-electron-diffraction (RHEED) intensity and compared with corresponding measurements during homoepitaxy of GaAs(100)3. An example of this behavior is shown in fig. 1. Panel (a) shows the behavior of the effective migration length of a typical Ga atom during the course of growth of a given atomic layer (the even numbered layers not shown correspond to As layers in this, the [100], growth case. Note the time dependent nature. Panels (b) and (c) show the dynamics of <W> and σh. Note the oscillatory nature, the time period coinciding with the growth time of a monolayer. The former shows damping, indicative of a growth kinetics control-led roughening in the growth front. This is confirmed by the increase in the average value of the latter. An overall measure of the surface smoothness which combines lateral (i.e. <W>) and vertical
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