Structural and compositional evolutions of InxAl1−xN core–shell nanorods grown on Si(111) substrates by reactive magnetron sputter epitaxy. (6th May 2015)

• Record Type: Journal Article
• Authors: Serban, Elena Alexandra; Åke Persson, Per Ola; Poenaru, Iuliana; Junaid, Muhammad; Hultman, Lars; Birch, Jens; Hsiao, Ching-Lien
• Is Part Of: Nanotechnology. Volume 26:Number 21(2015)
• Publication Date: 2015-05-06
• Subjects: InAlN -- core-shell -- nanorods -- sputtering -- MSE -- STEM -- EDX; Nanotechnology -- Periodicals; Nanotechnology -- Periodicals; Nanotechnology; Publications périodiques; Nanotechnologies; Periodicals; 620.5
• DOI: 10.1088/0957-4484/26/21/215602
• Languages: English
• ISSNs: 0957-4484

Abstract

Abstract: Catalystless growth of In x Al1− x N core–shell nanorods have been realized by reactive magnetron sputter epitaxy onto Si(111) substrates. The samples were characterized by scanning electron microscopy, x-ray diffraction, scanning transmission electron microscopy, and energy dispersive x-ray spectroscopy. The composition and morphology of In x Al1− x N nanorods are found to be strongly influenced by the growth temperature. At lower temperatures, the grown materials form well-separated and uniform core–shell nanorods with high In-content cores, while a deposition at higher temperature leads to the formation of an Al-rich In x Al1− x N film with vertical domains of low In-content as a result of merging Al-rich shells. The thickness and In content of the cores (domains) increase with decreasing growth temperature. The growth of the In x Al1− x N is traced to the initial stage, showing that the formation of the core–shell nanostructures starts very close to the interface. Phase separation due to spinodal decomposition is suggested as the origin of the resultant structures. Moreover, the in-plane crystallographic relationship of the nanorods and substrate was modified from a fiber textured to an epitaxial growth with an epitaxial relationship of In x Al1− x N[0001]//Si[111] and In x Al1− x N[11 ]//Si[1 by removing the native SiO x layer from the substrate.