Critical thickness as a function of the indium molar fraction in cubic InXGa1-XN and the influence in the growth of nanostructures. (15th August 2020)

• Record Type: Journal Article
• Authors: Compeán-García, V.D.; Hernández-Vázquez, O.; García-Hernández, S.A.; Luna, E.López; Vidal, M.A.
• Is Part Of: Materials science in semiconductor processing. Volume 115(2020)
• Publication Date: 2020-08-15
• Subjects: InXGa1-XN -- Cubic GaN -- Critical thickness -- III-Nitrides -- β-InXGa1-XN nanostructures; Semiconductors -- Periodicals; Integrated circuits -- Materials -- Periodicals; Semiconducteurs -- Périodiques; Circuits intégrés -- Matériaux -- Périodiques; Electronic journals; 621.38152
• DOI: 10.1016/j.mssp.2020.105101
• Languages: English
• ISSNs: 1369-8001

Abstract

Abstract: The critical thickness for the relaxation of cubic (β) InX Ga1-X N layers grown over (002) β-GaN/MgO, with different indium content, particularly of 17, 44, and 70% have been determined experimentally. The layers were grown by plasma-assisted molecular beam epitaxy. In all the samples studied, the critical thickness (hc) of the pseudomorphic layer was measured with a frame-by-frame analysis of reflection high energy electron diffraction (RHEED) patterns. The growth mode transition during layer growth was identified via RHEED patterns, from layer by layer or 2D to 3D growth mode by gradually transitioning from a streaky to a spotty pattern. The experimental hc value of β-InX Ga1-X N on β-GaN was compared to values calculated from the Fisher model. For the indium concentration of x = 0.44, the self-assembling epitaxial nanostructures were successfully grown in the Stranski–Krastanov growth mode with a critical thickness of 1.8 ± 0.7 nm. The β-In0.44 Ga0.56 N nanostructures showed a variation in morphology and density depending on the deposition time; self-assembled nanodots and nano-bars were confirmed by atomic force microscopy. Photoluminescence spectra of β-In0.44 Ga0.56 N nanostructures showed emissions associated with quantum confinement; these peaks indicate a blue shift with respect to the bulk.