Site-controlled growth of InP/GaInP quantum dots on GaAs substrates

摘要

A technology platform for the epitaxial growth of site-controlled InP quantum dots (QDs) on GaAs substrates is presented. Nanoholes are patterned in a GaInP layer on a GaAs substrate by electron beam lithography and dry chemical etching, serving as QD nucleation centers. The effects of a thermal treatment on the structured surfaces for deoxidation are investigated in detail. By regrowth on these surfaces, accurate QD positioning is obtained for square array arrangements with lattice periods of 1.25μm along with a high suppression of interstitial island formation. The optical properties of these red-emitting QDs (λ670nm) are investigated by means of ensemble- and micro- photoluminescence spectroscopy at cryogenic temperatures.