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Title: Metastability and relaxation in tensile SiGe on Ge(001) virtual substrates

We systematically study the heteroepitaxy of SiGe alloys on Ge virtual substrates in order to understand strain relaxation processes and maximize the tensile strain in the SiGe layer. The degree of relaxation is measured by high-resolution x-ray diffraction, and surface morphology is characterized by atomic force microscopy. The results are analyzed in terms of a numerical model, which considers dislocation nucleation, multiplication, thermally activated glide, and strain-dependent blocking. Relaxation is found to be sensitive to growth rate and substrate temperature as well as epilayer misfit and thickness, and growth parameters are found which allow a SiGe film with over 4 GPa of tensile stress to be obtained.
Authors:
; ; ; ;  [1] ;  [2]
  1. L-NESS, Dipartimento di Fisica, Politecnico di Milano, Polo di Como, via Anzani 42, 22100 Como (Italy)
  2. IFN-CNR, L-NESS, via Anzani 42, 22100 Como (Italy)
Publication Date:
OSTI Identifier:
22305992
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 11; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ATOMIC FORCE MICROSCOPY; CRYSTAL GROWTH; DISLOCATIONS; FILMS; GERMANIUM; GERMANIUM SILICIDES; INTERFACES; LAYERS; PRESSURE RANGE GIGA PA; RELAXATION; RESOLUTION; STRAINS; STRESSES; SUBSTRATES; SURFACES; THICKNESS; X-RAY DIFFRACTION