Sizes of Surface and Capped InxGa1-xAs/GaAs Quantum Dots

A report describes an experimental study of the sizes and concentrations of capped (buried) and surface In0.6Ga0.4As/GaAs quantum dots that were grown by metal-organic vapor deposition under the same conditions except for the inclusion or exclusion of capping. [InxGa1-xAs/GaAs quantum dots are lens-shaped islands (typically a few nanometers thick and tens of nanometers in diameter) of InxGa1-xAs grown on a GaAs substrate. As used here, "capping" signifies the growth of a layer of GaAs over the InxGa1-xAs islands.] In the experiments, the sizes of the capped In0.6Ga0.4As/GaAs islands were measured by transmission electron microscopy (TEM).