Self-organized formation and self-repair of a two-dimensionalnanoarray of Ge quantum dots epitaxially grown on ultrathinSiO2-covered Si substrates

Abstract

Two-dimensional nanoarrays of Ge quantum dots (QDs) with the ability to self-repairwere epitaxially grown by self-organization on Si substrates using an ultrathinSiO2 film technique. Nanometer-sized voids were patterned on ultrathinSiO2 films by transcription of the pattern of block copolymer films using a selective etchingmethod and worked as nucleation sites for QD growth. The epitaxial QDs wereelastically strain-relaxed without misfit dislocations and of uniform size. The epitaxialstructures of Si-capped QD nanoarrays exhibited strong photoluminescence near1.5 µm.