Journal
SEMICONDUCTOR SCIENCE AND TECHNOLOGY
Volume 33, Issue 12, Pages -Publisher
IOP PUBLISHING LTD
DOI: 10.1088/1361-6641/aae7b8
Keywords
molecular beam epitaxy; transmission electron microscopy; photoluminescence spectroscopy; axial GaAsSb nanowires
Categories
Funding
- US Office of Naval Research [N00014-16-1-2720]
- National Science Foundation [ECCS-1542015, ECCS-1542174]
- State of North Carolina
Ask authors/readers for more resources
The advancement of ternary GaAsSb mismatched alloy system toward the Sb-rich corner of the phase diagram in the nanowire (NW) configuration on silicon remains a challenge. A large lattice mismatch between the silicon substrate and GaAsSb with an Sb-rich composition, along with the low supersaturation and low solubility of Sb in the Ga droplet in the vapor-liquid-solid growth mechanism, causes significant issues during Ga-assisted molecular beam epitaxial growth of these NWs. In this work, we have carried out a systematic study of Sb-rich GaAs1-x Sbx NWs grown on Si (111) using variations of the Ga, As, and Sb beam equivalent pressures (BEP) to minimize undesirable parasitic growth and achieve photoemission up to 1.7 mu m. Ga-assisted molecular beam epitaxy is the enabling growth technology for the growth of these self-catalyzed GaAs1-x Sbx, (x > 0.8) NWs. The use of a dual substrate temperature approach along with low As background pressure and a low Ga BEP were found to be the key growth components in achieving a well-faceted NW morphology with a low parasitic layer on the substrate. Energy-dispersive x-ray spectroscopy analysis confirms uniform compositional homogeneity along the NWs, while selected-area electron diffraction patterns in the transmission electron microscope revealed a zinc-blende crystal structure. A peak it-photoluminescence emission of 1680 nm with a narrow FWHM was obtained at 4 K. Raman spectra at room temperature exhibit only GaSb related LO and TO modes, which attest to the high quality of the NWs grown. This is a promising approach due to the broad scope of applicability to grow other mismatched alloy material systems in a NW configuration.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available