The role of the InGaAs surface in selective area epitaxy of quantum dots by indium segregation

The surface of strained InGaAs films for selective regrowth of InAs nanostructures is investigated by atomic force microscopy and Rutherford backscattering. 3.3-nm-thick In0.33Ga0.67As films were annealed at temperatures between 400 and 800 °C. Significant indium desorption was found to occur at temperatures above 550 °C. The optimum parameters are presented for selective growth of InAs quantum dots having densities of 6.6×1010 cm−2 on In0.33Ga0.67As films.