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Title: Lattice-engineered Si{sub 1-x}Ge{sub x}-buffer on Si(001) for GaP integration

We report a detailed structure and defect characterization study on gallium phosphide (GaP) layers integrated on silicon (Si) (001) via silicon-germanium (SiGe) buffer layers. The presented approach uses an almost fully relaxed SiGe buffer heterostructure of only 400 nm thickness whose in-plane lattice constant is matched to GaP—not at room but at GaP deposition temperature. Single crystalline, pseudomorphic 270 nm thick GaP is successfully grown by metalorganic chemical vapour deposition on a 400 nm Si{sub 0.85}Ge{sub 0.15}/Si(001) heterosystem, but carries a 0.08% tensile strain after cooling down to room temperature due to the bigger thermal expansion coefficient of GaP with respect to Si. Transmission electron microscopy (TEM) studies confirm the absence of misfit dislocations in the pseudomorphic GaP film but growth defects (e.g., stacking faults, microtwins, etc.) especially at the GaP/SiGe interface region are detected. We interpret these growth defects as a residue of the initial 3D island coalescence phase of the GaP film on the SiGe buffer. TEM-energy-dispersive x-ray spectroscopy studies reveal that these defects are often correlated with stoichiometric inhomogeneities in the GaP film. Time-of-flight Secondary ion mass spectrometry detects sharp heterointerfaces between GaP and SiGe films with a minor level of Ga diffusion into the SiGe buffer.
Authors:
; ; ;  [1] ; ;  [2] ; ;  [3] ;  [4] ;  [1] ;  [5] ;  [1] ;  [5]
  1. IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany)
  2. Technische Universität Ilmenau, Gustav-Kirchhoff-Str. 5, 98693 Ilmenau (Germany)
  3. Institut für Physik, Humboldt Universität zu Berlin, Newtonstrasse 15, 12489 Berlin (Germany)
  4. Paul Drude Institut für Festkörperelektronik, Hausvogteiplatz 5-7, 10117 Berlin (Germany)
  5. (Germany)
Publication Date:
OSTI Identifier:
22277911
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 115; Journal Issue: 10; 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; CHEMICAL VAPOR DEPOSITION; COALESCENCE; DIFFUSION; DISLOCATIONS; GALLIUM PHOSPHIDES; GERMANIUM; GERMANIUM SILICIDES; INTERFACES; LATTICE PARAMETERS; LAYERS; MASS SPECTROSCOPY; MONOCRYSTALS; SILICON; STACKING FAULTS; TEMPERATURE RANGE 0273-0400 K; THERMAL EXPANSION; THIN FILMS; TIME-OF-FLIGHT METHOD; TRANSMISSION ELECTRON MICROSCOPY; X-RAY SPECTROSCOPY