No data available.
Please log in to see this content.
You have no subscription access to this content.
No metrics data to plot.
The attempt to load metrics for this article has failed.
The attempt to plot a graph for these metrics has failed.
The full text of this article is not currently available.
Raman spectroscopy based measurements of carrier concentration in n-type GaN nanowires grown by plasma-assisted molecular beam epitaxy
G. Irmer, V. V. Toporov, B. H. Bairamov, and J. Monecke, “ Determination of the charge carrier concentration and mobility in n-GaP by Raman spectroscopy,” Phys. Status Solidi B 119, 595 (1983).
K. Jeganathan, R. K. Debnath, R. Meijers, T. Stoica, R. Calarco, D. Grützmacher, and H. Lüth, “ Raman scattering of phonon-plasmon coupled modes in self-assembled GaN nanowires,” J. Appl. Phys. 107, 123707 (2009).
D. Wang, C.-C. Tin, J. R. Williams, M. Park, Y. S. Park, C. M. Park, T. W. Kang, and W.-C. Yang, “ Raman characterization of electronic properties of self-assembled GaN nanorods grown by plasma-assisted molecular-beam epitaxy,” Appl. Phys. Lett. 87, 242105 (2005).
T. Kozawa, T. Kachi, H. Kano, Y. Taga, M. Hashimoto, N. Koide, and K. Manabe, “ Raman scattering from LO phonon-plasmon coupled modes in gallium nitride,” J. Appl. Phys. 75, 1098 (1994).
R. Katayama, Y. Kuge, K. Onabe, T. Matsushita, and T. Kondo, “ Complementary analyses on the local polarity in lateral polarity-inverted GaN heterostructure on sapphire (0001) substrate,” Appl. Phys. Lett. 89, 231910 (2006).
C. Wetzel, W. Walukiewicz, E. E. Haller, J. Ager III, I. Grzegory, S. Porowski, and T. Suski, “ Carrier localization of as-grown n-type gallium nitride under large hydrostatic pressure,” Phys. Rev. B 53, 1322 (1996).
M. Yoon, I.-W. Park, H. Choi, S. S. Park, and E. K. Koh, “ Free carrier concentration gradient along the c-axis of a freestanding Si-doped GaN single crystal,” Jpn. J. Appl. Phys., Part 1 44, 828 (2005).
R. Cuscó, N. Domènech-Amador, L. Artús, T. Gotschke, K. Jeganathan, T. Stoica, and R. Calarco, “ Probing the electron density in undoped, Si-doped, and Mg-doped InN nanowires by means of Raman scattering,” Appl. Phys. Lett. 97, 221906 (2010).
P. Parkinson, C. Dodson, H. J. Joyce, K. A. Bertness, N. A. Sanford, L. M. Herz, and M. B. Johnston, “ Noncontact measurement of charge carrier lifetime and mobility in GaN nanowires,” Nano Lett. 12, 4600 (2012).
J. L. Boland, S. Conesa-Boj, P. Parkinson, G. Tuütuüncuüoglu, F. Matteini, D. Ruüffer, A. Casadei, F. Amaduzzi, F. Jabeen, C. L. Davies, H. J. Joyce, L. M. Herz, A. Fontcuberta-i-Morral, and M. B. Johnston, “ Modulation doping of GaAs/AlGaAs core−shell nanowires with effective defect passivation and high electron mobility,” Nano Lett. 15, 1336 (2015).
B. Ketterer, E. Uccelli, and A. Fontcuberta-i-Morral, “ Mobility and carrier density in p-type GaAs nanowires measured by transmission Raman spectroscopy,” Nanoscale 4, 1789 (2012).
F. Wang, Q. Gao, K. Peng, Z. Li, Z. Li, Y. Guo, L. Fu, L. M. Smith, H. H. Tan, and C. Jagadish, “ Spatially resolved doping concentration and nonradiative lifetime profiles in single Si-doped InP nanowires using photoluminescence mapping,” Nano Lett. 15, 3017 (2015).
V. Laneuville, F. Demangeot, R. Péchou, P. Salles, A. Ponchet, K. March, L. F. Zagonel, and R. Songmuang, “ Double strain state in a single GaN/AlN nanowire: Probing the core-shell effect by ultraviolet resonant Raman scattering,” Phys. Rev. B 83, 115417 (2011).
P. J. Pauzauskie, D. Talaga, K. Seo, P. Yang, and F. Francüois Lagugné-Labarthet, “ Polarized Raman confocal microscopy of single gallium nitride nanowires,” J. Am. Chem. Soc. 127, 17146 (2005).
N. A. Sanford, L. H. Robins, P. T. Blanchard, K. Soria, B. Klein, B. S. Eller, K. A. Bertness, J. B. Schlager, and A. W. Sanders, “ Studies of photoconductivity and field effect transistor behavior in examining drift mobility, surface depletion, and transient effects in Si-doped GaN nanowires in vacuum and air,” J. Appl. Phys. 113, 174306 (2013).
N. A. Sanford, L. H. Robins, A. V. Davydov, A. Shapiro, D. V. Tsvetkov, A. V. Dmitriev, S. Keller, U. K. Mishra, and S. P. DenBaars, “ Refractive index study of AlxGa1−xN films grown on sapphire substrates,” J. Appl. Phys. 94, 2980 (2003).
S. Pezzagna, J. Brault, M. Leroux, J. Massies, and M. de Micheli, “ Refractive indices and elasto-optic coefficients of GaN studied by optical waveguiding,” J. Appl. Phys. 103, 123112 (2008).
V. Yu. Davydov, Yu. E. Kitaev, I. N. Goncharuk, A. N. Smirnov, J. Graul, O. Semchinova, D. Uffmann, M. B. Smirnov, A. P. Mirgorodsky, and R. A. Evarestov, “ Phonon dispersion and Raman scattering in hexagonal GaN and AlN,” Phys. Rev. B 58, 12899 (1998).
K. A. Bertness, A. Roshko, L. M. Mansfield, T. E. Harvey, and N. A. Sanford, “ Mechanism for spontaneous growth of GaN nanowires with molecular beam epitaxy,” J. Cryst. Growth 310, 3154 (2008).
C. T. Foxon, I. Harrison, S. V. Novikov, A. J. Winser, R. P. Campion, and T. Li, “ The growth and properties of GaN:As layers prepared by plasma-assisted molecular beam epitaxy,” J. Phys.: Condens. Matter 14, 3383 (2002).
K. A. Bertness, M. D. Brubaker, T. E. Harvey, S. M. Duff, A. W. Sanders, and N. A. Sanford, “ In situ temperature measurements for selective epitaxy of GaN nanowires,” Phys. Status Solidi C 11, 590 (2014).
Commercial equipment, instruments, or materials are identified only in order to adequately specify certain procedures. In no case does such identification imply recommendation or endorsement by the National Institute of Standards and Technology, nor does it imply that the products identified are necessarily the best available for the purpose.
H. Siegle, G. Kaczmarczyk, L. Filippidis, A. P. Litvinchuk, A. Hoffmann, and C. Thomsen, “ Zone-boundary phonons in hexagonal and cubic GaN,” Phys. Rev. B 55, 7000 (1997).
L. H. Dubois and G. P. Schwartz, “ Surface optical phonons and hydrogen chemisorption on polar and nonpolar faces of GaAs, GaP, and InP,” Phys. Rev. B 26, 794 (1982).
H. C. Guo, X. H. Zhang, W. Liu, A. M. Yong, and S. H. Tang, “ Terahertz carrier dynamics and dielectric properties of GaN epilayers with different carrier concentrations,” J. Appl. Phys. 106, 063104 (2009).
L. M. Mansfield, K. A. Bertness, P. T. Blanchard, T. E. Harvey, A. W. Sanders, and N. A. Sanford, “ GaN nanowire carrier concentration calculated from light and dark resistance measurements,” J. Electron. Mater. 38, 495 (2009).
P. T. Blanchard, K. A. Bertness, T. E. Harvey, L. M. Mansfield, A. W. Sanders, and N. A. Sanford, “ MESFETs made from individual GaN nanowires,” IEEE Trans. Nanotechnol. 7, 760 (2008).
A. Henning, B. Klein, K. A. Bertness, P. T. Blanchard, N. A. Sanford, and Y. Rosenwaks, “ Measurement of the electrostatic edge effect in wurtzite GaN nanowires,” Appl. Phys. Lett. 105, 213107 (2014).
J. Wang, F. Demangeot, R. Péchou, C. Bayon, A. Mlayah, and B. Daudin, “ Size and shape effects in the Raman scattering by single GaN nanowires,” J. Appl. Phys. 114, 223506 (2013).
N. A. Sanford, P. T. Blanchard, K. A. Bertness, L. Mansfield, J. B. Schlager, A. W. Sanders, A. Roshko, B. B. Burton, and S. M. George, “ Steady-state and transient photoconductivity in c-axis GaN nanowires grown by nitrogen-plasma-assisted molecular beam epitaxy,” J. Appl. Phys. 107, 034318 (2010).
J. B. Schlager, N. A. Sanford, K. A. Bertness, J. M. Barker, A. Roshko, and P. T. Blanchard, “ Polarization-resolved photoluminescence study of individual GaN nanowires grown by catalyst-free molecular beam epitaxy,” Appl. Phys. Lett. 88, 213106 (2006).
D. C. Montgomery and G. C. Runger, Applied Statistics and Probability for Engineers ( John Wiley and Sons, 1999); see in particular the following sections: 7-7 “Introduction on Confidence Intervals,” 8-3 “Inference on the Mean of a Population, Variance Unknown,” Appendix A Table IV, “Percentage Points of the t-Distribution,” Appendix B-IV, “Development of the t- and F-distributions”.
L. Filippidis, H. Siegle, A. Hoffmann, C. Thomsen, K. Karch, and F. Bechstedt, “ Raman frequencies and angular dispersion of polar modes in aluminum nitride and gallium nitride,” Phys. Status Solidi B 198, 621 (1996).
L. Bergman, M. Dutta, C. Balkas, R. F. Davis, J. A. Christman, D. Alexson, and R. J. Nemanich, “ Raman analysis of the E1 and A1 quasi-longitudinal optical and quasi-transverse optical modes in wurtzite AlN,” J. Appl. Phys. 85, 3535 (1999).
T. Azuhata, M. Ono, K. Torii, T. Sota, S. F. Chichibu, and S. Nakamura, “ Forward Raman scattering by quasilongitudinal optical phonons in GaN,” J. Appl. Phys. 88, 5202 (2000).
Article metrics loading...
The carrier concentration in as-grown ensembles of n-type GaN nanowires was determined by Raman spectroscopy of the coupled longitudinal phonon–plasmon (LPP+) mode and modeling of the carrier concentration dependence of the LPP+ frequency. The Raman measurements and analyses enabled estimation of the carrier concentration in single-nanowire devices fabricated from the as-grown ensembles. The nanowires were grown by plasma-assisted molecular beam epitaxy in either of the two growth systems. Twelve samples were examined, of which 11 samples were Si-doped and one was undoped. The Raman-measured carrier concentrations in the Si-doped samples ranged from (5.28 ± 1.19) × 1016 cm−3 to (6.16 ± 0.35) × 1017 cm−3. For a subset of samples grown with varying Si cell temperature, from 1125 °C to 1175 °C, the carrier concentration was found to be an Arrhenius function of Si cell temperature, with activation energy of Co-illumination by an above band gap UV laser (325 nm, excitation intensity = 0.7 W/cm2 or 4.5 W/cm2) induced small increases in carrier concentration, relative to illumination by the Raman excitation laser alone (633 nm, excitation intensity ≈100 kW/cm2). The lowest Si-doped sample showed the largest increase in carrier concentration, (6.3 ± 4.8) × 1015 cm−3 with UV excitation intensity of 0.7 W/cm2. These results imply that, even in the absence of UV illumination, surface depletion does not have a significant effect on the Raman carrier concentration measurements. Immersion in a high-dielectric-constant oil (ε = 2.24) caused downshifts of similar magnitude in the LPP+ frequencies of undoped and doped nanowires. This result implies that the LPP+ mode has bulk plasmon rather than surface plasmon character, because immersion in a high-dielectric-constant medium is predicted to cause a large decrease in the surface plasmon frequency, which would induce a larger LPP+ downshift in doped than undoped nanowires. A surface optical (SO) phonon peak was observed in each sample in air at ≈96.4% of the LPP+ frequency. The SO frequency decreased to ≈93.1% of the LPP+ frequency upon oil immersion, as predicted by a simple dielectric model.
Full text loading...
Most read this month