Quantum confined nanostructures with improved homogeneity and methods for making the same

Abstract

A method that includes: providing a substrate including a layer of a crystalline material having a first surface; and exposing the first surface to an environment under conditions sufficient to cause epitaxial growth of a layer of a deposition material on the first surface, wherein exposing the first surface to the environment includes illuminating the substrate with light at a first wavelength while causing the epitaxial growth of the layer of the deposition material. The first surface includes one or more discrete growth sites at which an epitaxial growth rate of the quantum confined nanostructure material is larger than areas of the first surface away from the growth sites by an amount sufficient so that the deposition material forms a quantum confined nanostructure at each of the one or more discrete growth sites.

What is claimed is: 
     
         1 . An article, comprising:
 a substrate comprising a layer of a crystalline material, the layer of the crystalline material comprising locations of increased strain in the crystalline material relative to strain in the crystalline material away from the locations; and   a quantum confined nanostructure layer supported by the substrate and in contact with a surface of the layer of the crystalline material, the quantum confined nanostructure layer comprising one or more quantum confined nanostructures each comprising a layer of an epitaxial crystalline material, each of the one or more quantum confined nanostructures being located at a corresponding one of the locations of increased strain in the layer of the crystalline material,   wherein each quantum confined nanostructure has a dimension corresponding to a first wavelength and the substrate comprises a layer that substantially absorbs light at the first wavelength.   
     
     
         2 . The article of  claim 1 , wherein the substrate further comprises a second layer adjacent to the layer of the crystalline material, the crystalline layer being an epitaxial layer and second layer comprising portions having a first composition and portions having a second composition different from the first composition, the variation in composition of the second layer causing the locations of increased strain in the crystalline material. 
     
     
         3 . The article of  claim 1 , wherein the quantum confined nanostructures are quantum dots or quantum dashes. 
     
     
         4 . The article of  claim 1 , wherein the quantum confined nanostructures each have an anisotropic shape having a long dimension and a short dimension orthogonal to the long dimension. 
     
     
         5 . The article of  claim 4 , wherein the long dimension of each quantum confined nanostructure lies parallel to a common axis.