Abstract: A method of at least partially releasing an epitaxial layer of a material from a substrate. The method comprises the steps of: forming a patterned sacrificial layer on the substrate such that the substrate is partially exposed and partially covered by the sacrificial layer; growing the epitaxial layer on the patterned sacrificial layer by nano-epitaxial lateral overgrowth such that the epitaxial layer is formed above an intermediate layer comprising the patterned sacrificial layer and said material; and selectively etching the patterned sacrificial layer such that the epitaxial layer is at least partially released from the substrate.

Abstract: The present invention relates to a photonic device comprising a plurality of nanostructures that extend from a substrate, each nanostructure comprising a generally longitudinal nanostructure body formed of a semiconductor material. Each nanostructure has a proximal end portion of a first crystal lattice structure and a distal end portion of a second crystal lattice structure that is expanded relative to the proximal end portion. Each nanostructure further comprises an optically active material optically associated with the distal end portion to form a heterojunction therebetween. The present invention further relates to a method of making the disclosed nanostructures.

Abstract: A method of at least partially releasing an epitaxial layer of a material from a substrate. The method comprises the steps of: forming a patterned sacrificial layer on the substrate such that the substrate is partially exposed and partially covered by the sacrificial layer; growing the epitaxial layer on the patterned sacrificial layer by nano-epitaxial lateral overgrowth such that the epitaxial layer is formed above an intermediate layer comprising the patterned sacrificial layer and said material; and selectively etching the patterned sacrificial layer such that the epitaxial layer is at least partially released from the substrate.

Abstract: A technique for growing a high quality gallium nitride layer on a uniform nano-patterned substrate is described. The invented technique is based on the transfer of ordered nano-patterns from a nano-template to the substrate, followed by the growth of gallium nitride on the nano-patterned substrate. The nano-patterned substrate serves as a buffer layer to reduce the stress and dislocations.