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Title: Growth of GaAs{sub 1−x}Bi{sub x} by molecular beam epitaxy: Trade-offs in optical and structural characteristics

Recent work has shown that Bi incorporation increases during molecular beam epitaxy (MBE) when surface processes are kinetically limited through increased growth rate. Herein we explore how the structural and optical properties of GaAs{sub 1−x}Bi{sub x} films are modified when grown under conditions with varying degrees of kinetic limitations realized through growth temperature and growth rate changes. Within the typical window of MBE growth conditions for GaAs{sub 1−x}Bi{sub x}, we compare films with similar (∼3%) compositions grown under conditions of reduced kinetic limitations, i.e., relatively low gallium supersaturation achieved at higher temperatures (∼350 °C) and lower growth rates (∼0.5 μm/h), to those grown farther from equilibrium, specifically, higher supersaturation achieved at lower growth temperatures (∼290 °C) and higher growth rates (∼1.4 μm/h). Both the x-ray diffraction full width at half maximum of the omega-2theta scan and the 300 K photoluminescence intensity increase when samples are grown under less kinetically limited conditions. We interpret these findings in relation to the incorporation of Bi-related microstructural defects that are more readily formed during less kinetically limited growth. These defects lead to enhanced luminescence efficiency due to the spatial localization of carriers.
Authors:
; ; ; ;  [1] ;  [2] ;  [3] ;  [4] ;  [2]
  1. Department of Electrical and Computer Engineering, Duke University, Durham, North Carolina 27708 (United States)
  2. Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States)
  3. (United States)
  4. Department of Physics, Duke University, Durham, North Carolina 27708 (United States)
Publication Date:
OSTI Identifier:
22308527
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 4; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; BISMUTH COMPOUNDS; CARRIERS; CRYSTAL DEFECTS; CRYSTAL GROWTH; EFFICIENCY; EQUILIBRIUM; FILMS; GALLIUM ARSENIDES; MICROSTRUCTURE; MOLECULAR BEAM EPITAXY; OPTICAL PROPERTIES; PHOTOLUMINESCENCE; SUPERSATURATION; SURFACES; X-RAY DIFFRACTION