Surface optical phonons in GaAs nanowires grown by Ga-assisted chemical beam epitaxy
Journal Article
·
· Journal of Applied Physics
- Grupo de Electrónica y Semiconductores, Departamento de Física Aplicada, Universidad Autónoma de Madrid, 28049 Madrid (Spain)
- Department of Electrical and Computer Engineering, The University of Alabama, Tuscaloosa, Alabama 35487 (United States)
Surface optical (SO) phonons were studied by Raman spectroscopy in GaAs nanowires (NWs) grown by Ga-assisted chemical beam epitaxy on oxidized Si(111) substrates. NW diameters and lengths ranging between 40 and 65 nm and between 0.3 and 1.3 μm, respectively, were observed under different growth conditions. The analysis of the Raman peak shape associated to either longitudinal or surface optical modes gave important information about the crystal quality of grown NWs. Phonon confinement model was used to calculate the density of defects as a function of the NW diameter resulting in values between 0.02 and 0.03 defects/nm, indicating the high uniformity obtained on NWs cross section size during growth. SO mode shows frequency downshifting as NW diameter decreases, this shift being sensitive to NW sidewall oxidation. The wavevector necessary to activate SO phonon was used to estimate the NW facet roughness responsible for SO shift.
- OSTI ID:
- 22275683
- Journal Information:
- Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 3 Vol. 115; ISSN JAPIAU; ISSN 0021-8979
- Country of Publication:
- United States
- Language:
- English
Similar Records
Structural characterization of GaAs and InAs nanowires by means of Raman spectroscopy
Onset of stacking faults in InP nanowires grown by gas source molecular beam epitaxy
Bandgap measurements and the peculiar splitting of E{sub 2}{sup H} phonon modes of In{sub x}Al{sub 1-x}N nanowires grown by plasma assisted molecular beam epitaxy
Journal Article
·
Fri Nov 14 23:00:00 EST 2008
· Journal of Applied Physics
·
OSTI ID:21185932
Onset of stacking faults in InP nanowires grown by gas source molecular beam epitaxy
Journal Article
·
Sun Dec 31 23:00:00 EST 2006
· Applied Physics Letters
·
OSTI ID:20883257
Bandgap measurements and the peculiar splitting of E{sub 2}{sup H} phonon modes of In{sub x}Al{sub 1-x}N nanowires grown by plasma assisted molecular beam epitaxy
Journal Article
·
Thu Jul 28 00:00:00 EDT 2016
· Journal of Applied Physics
·
OSTI ID:22597790