Format

Send to

Choose Destination
See comment in PubMed Commons below
Nanoscale Res Lett. 2009 Aug 30;4(12):1458-62. doi: 10.1007/s11671-009-9420-9.

Structural Analysis of Highly Relaxed GaSb Grown on GaAs Substrates with Periodic Interfacial Array of 90° Misfit Dislocations.

Author information

  • 1Electrical Engineering Department, University of California at Los Angeles, Los Angeles, CA, 90095, USA. anitha@ucla.edu.

Abstract

We report structural analysis of completely relaxed GaSb epitaxial layers deposited monolithically on GaAs substrates using interfacial misfit (IMF) array growth mode. Unlike the traditional tetragonal distortion approach, strain due to the lattice mismatch is spontaneously relieved at the heterointerface in this growth. The complete and instantaneous strain relief at the GaSb/GaAs interface is achieved by the formation of a two-dimensional Lomer dislocation network comprising of pure-edge (90°) dislocations along both [110] and [1-10]. In the present analysis, structural properties of GaSb deposited using both IMF and non-IMF growths are compared. Moiré fringe patterns along with X-ray diffraction measure the long-range uniformity and strain relaxation of the IMF samples. The proof for the existence of the IMF array and low threading dislocation density is provided with the help of transmission electron micrographs for the GaSb epitaxial layer. Our results indicate that the IMF-grown GaSb is completely (98.5%) relaxed with very low density of threading dislocations (105 cm-2), while GaSb deposited using non-IMF growth is compressively strained and has a higher average density of threading dislocations (>109 cm-2).

KEYWORDS:

GaSb/GaAs; Interfacial misfit dislocations (IMF) or Lomer dislocations; Moiré fringes; Molecular beam epitaxy; Semiconductor; Strain relief; Structural properties

PMID:
20652143
PMCID:
PMC2894098
DOI:
10.1007/s11671-009-9420-9
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Springer Icon for PubMed Central
    Loading ...
    Support Center