Desorption and Segregation of Indium and its Dependence on Surface As-coverage

<jats:title>Abstract</jats:title><jats:p>We investigate the desorption and segregation rates of Indium atoms on fully strained In<jats:sub>x</jats:sub>Ga<jats:sub>l-x</jats:sub>As surfaces and their dependence on the surface As-coverage. The results are obtained by measuring the desorption of As using reflection high energy electron diffraction. The desorption rate of As is sensitive to the interaction energies between the group III atoms and the As-atoms. A change in the surface Indium-fraction results in a corresponding change in the desorption behavior of the As-atoms. Information of the surface alloy concentration can thus be obtained. Using this technique we find that segregation and desorption of Indium atoms on strained In<jats:sub>x</jats:sub>Ga<jats:sub>1-x</jats:sub>As surfaces is reduced for As-covered 2x4 reconstructed surfaces. The desorption rate of Indium is found to increase with the proximity to an inverted InAs/In<jats:sub>x</jats:sub>Gal<jats:sub>x</jats:sub>As interface. In contrast, the normal interface consisting of an In<jats:sub>x</jats:sub>Ga<jats:sub>l-x</jats:sub>As layer grown on InAs is not seen to influence the desorption rate. This results is attributed to growth related defects specific for the inverted interface.</jats:p>