Bandgap measurements and the peculiar splitting of E2H phonon modes of InxAl1-xN nanowires grown by plasma assisted molecular beam epitaxy

The dislocation free InxAl1-xN nanowires (NWs) are grown on Si(111) by nitrogen plasma assisted molecular beam epitaxy in the temperature regime of 490 °C–610 °C yielding In composition ranges over 0.50 ≤ x ≤ 0.17. We study the optical properties of these NWs by spectroscopic ellipsometry (SE), photoluminescence, and Raman spectroscopies since they possesses minimal strain with reduced defects comparative to the planar films. The optical bandgap measurements of InxAl1-xN NWs are demonstrated by SE where the absorption edges of the NW samples are evaluated irrespective of substrate transparency. A systematic Stoke shift of 0.04–0.27 eV with increasing x was observed when comparing the micro-photoluminescence spectra with the Tauc plot derived from SE. The micro-Raman spectra in the NWs with x = 0.5 showed two-mode behavior for A1(LO) phonons and single mode behavior for E2H phonons. As for x = 0.17, i.e., high Al content, we observed a peculiar E2H phonon mode splitting. Further, we observe composition dep...

[1]  S. M. Shivaprasad,et al.  Optical bandgap and near surface band bending in degenerate InN films grown by molecular beam epitaxy , 2013 .

[2]  J. Carlin,et al.  Al0.83In0.17N lattice-matched to GaN used as an optical blocking layer in GaN-based edge emitting lasers , 2009 .

[3]  G. Auner,et al.  Ultraviolet and visible resonance-enhanced Raman scattering in epitaxial Al1−xInxN thin films , 2001 .

[4]  Eugene E. Haller,et al.  Small band gap bowing in In1−xGaxN alloys , 2002 .

[5]  Jingbiao Cui,et al.  Noncontact temperature measurements of diamond by Raman scattering spectroscopy , 1998 .

[6]  M. Stroscio,et al.  Ultraviolet Raman study of A1(LO) and E2 phonons in InxGa1-xN alloys , 2001 .

[7]  Alexandros Georgakilas,et al.  Energy bandgap bowing of InAlN alloys studied by spectroscopic ellipsometry , 2008 .

[8]  K. Kishino,et al.  Low‐temperature photoluminescence studies of In‐rich InAlN nanocolumns , 2012 .

[9]  Steven Prawer,et al.  Temperature dependence of Raman scattering in single crystal GaN films , 1999 .

[10]  Marc Ilegems,et al.  Crack-free fully epitaxial nitride microcavity using highly reflective AlInN∕GaN Bragg mirrors , 2005 .

[11]  Shamsul Arafin,et al.  Review of recent progress of III-nitride nanowire lasers , 2013 .

[12]  G. Konstantinidis,et al.  InAlN/GaN HEMTs: a first insight into technological optimization , 2006, IEEE Transactions on Electron Devices.

[13]  Kai Cui,et al.  Temperature-dependent nonradiative recombination processes in GaN-based nanowire white-light-emitting diodes on silicon , 2012, Nanotechnology.

[14]  Nicolas Fressengeas,et al.  Bandgap energy bowing parameter of strained and relaxed InGaN layers , 2014 .

[15]  J. Pankove,et al.  Epitaxially grown AlN and its optical band gap , 1973 .

[16]  E. Haller,et al.  Band gap bowing parameter of In1−xAlxN , 2008 .

[17]  D. J. Lockwood,et al.  Optical phonons inAlxGa1−xAs: Raman spectroscopy , 2004 .

[18]  J. Hayes,et al.  Temperature Dependence of the Phonons of Bulk AlN , 2000 .

[19]  A. Yamamoto,et al.  Raman scattering of indium-rich Al x In 1 − x N : Unexpected two-mode behavior of A 1 ( LO ) , 2009 .

[20]  I. F. Chang,et al.  Application of a Modified Random-Element-Isodisplacement Model to Long-Wavelength Optic Phonons of Mixed Crystals , 1968 .

[21]  Michael Kneissl,et al.  III-Nitride Ultraviolet Emitters: Technology and Applications , 2015 .

[22]  S. M. Shivaprasad,et al.  Role of native defects in nitrogen flux dependent carrier concentration of InN films grown by molecular beam epitaxy , 2012 .

[23]  Michael Heuken,et al.  Optical, structural investigations and band-gap bowing parameter of GaInN alloys , 2009 .

[24]  N. Teraguchi,et al.  Growth of AlN films on SiC substrates by RF-MBE and RF-MEE , 2001 .

[25]  Cohen,et al.  Theory of electron band tails and the Urbach optical-absorption edge. , 1986, Physical review letters.

[26]  Y. Su,et al.  Improved Light Output of Nitride-Based Light-Emitting Diodes by Lattice-Matched AlInN Cladding Structure , 2008, IEEE Photonics Technology Letters.

[27]  J. Kuzmik,et al.  Power electronics on InAlN/(In)GaN: Prospect for a record performance , 2001, IEEE Electron Device Letters.

[28]  Pallab Bhattacharya,et al.  Monolithic electrically injected nanowire array edge-emitting laser on (001) silicon. , 2014, Nano letters.

[29]  E. Haller,et al.  On the crystalline structure, stoichiometry and band gap of InN thin films , 2004 .

[30]  H. Morkoç,et al.  Energy band bowing parameter in AlxGa1-xN alloys , 2002 .

[31]  B. Daudin,et al.  A geometrical model for the description of the AlN shell morphology in GaN-AlN core-shell nanowires , 2013 .

[32]  H. Renevier,et al.  Growth, structural and optical properties of AlGaN nanowires in the whole composition range , 2013, Nanotechnology.

[33]  Friedhelm Bechstedt,et al.  Phonons in ternary group-III nitride alloys , 2000 .

[34]  Igor A. Abrikosov,et al.  Lattice parameters, deviations from Vegard’s rule, and E2 phonons in InAlN , 2008 .

[35]  A. Yoshikawa,et al.  Growth and Characterization of AlInN Ternary Alloys in Whole Composition Range and Fabrication of InN/AlInN Multiple Quantum Wells by RF Molecular Beam Epitaxy , 2006 .

[36]  R. Leonelli,et al.  Recombination dynamics in InGaN/GaN nanowire heterostructures on Si(111) , 2013, Nanotechnology.

[37]  Hiroshi Harima,et al.  Absorption and Emission of Hexagonal InN. Evidence of Narrow Fundamental Band Gap. , 2002 .

[38]  Jay Ghatak,et al.  Electron mobility of self-assembled and dislocation free InN nanorods grown on GaN nano wall network template , 2016 .

[39]  Zetian Mi,et al.  Interplay of strain and indium incorporation in InGaN/GaN dot-in-a-wire nanostructures by scanning transmission electron microscopy , 2015, Nanotechnology.

[40]  S. Emura,et al.  Raman spectra of AlxIn1−xAs grown by molecular-beam epitaxy , 1987 .

[41]  Md. Zunaid Baten,et al.  Optical constants of In(x)Ga(1-x)N (0 ≤ x ≤ 0.73) in the visible and near-infrared wavelength regimes. , 2015, Optics letters.

[42]  M. Manfra,et al.  Optimized growth of lattice-matched InxAl1−xN∕GaN heterostructures by molecular beam epitaxy , 2007 .

[43]  Jeremy J. Baumberg,et al.  Current status of AlInN layers lattice-matched to GaN for photonics and electronics , 2007 .

[44]  A. N. Smirnov,et al.  Composition dependence of optical phonon energies and Raman line broadening in hexagonal Al x Ga 1 − x N alloys , 2002 .

[45]  Takashi Mukai,et al.  P-GaN/N-InGaN/N-GaN Double-Heterostructure Blue-Light-Emitting Diodes , 1993 .

[46]  E. Suh,et al.  Growth and properties of Al-rich InxAl1−xN ternary alloy grown on GaN template by metalorganic chemical vapour deposition , 2008 .