Valence band structure of InN from x-ray photoemission studies

Louis F. J. Piper 4Tim Veal 4Paul H. Jefferson 4Chris F. McConville 4Frank Fuchs 3J Furthmüller 3Friedhelm Bechstedt 3Hai Lu 2William J. Schaff 2Hiroyuki Naoi 1Y Nanishi 1

1. Ritsumeikan University (Rits), Kusatsu 525-8577, Japan
2. Cornell University, Electrical and Computer Engineering, Ithaca, NY 14853-540, United States
3. Freidrich-Schiller-Universitat Jena, Jena 07743, Germany
4. University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, United Kingdom


The band structure of InN has been investigated by comparing the calculated valence-band density of states with x-ray photoemission spectroscopy (XPS) of the valence-bands. The band structure of InN has previously been calculated using density functional theory (DFT) within the local density approximation (LDA) [1]. Such calculations result in an overlap of the conduction and valence bands around the Γ-point, giving rise to negative band gaps. The overlap is due to the overestimation of the pd-repulsion within the DFT-LDA [2]. Pseudo-potentials accounting for the self-interaction corrections of the In4d electrons were used to revise the amount of pd-repulsion, avoiding the overestimation [1]. The percentage contribution of the pd-repulsion was determined by comparing the experimental and theoretical positioning of the In4d valence-levels with respect to the valence band maximum (VBM). Here, the true experimental In4d - VBM separation is reported as 16.0 ± 0.2 eV, in contrast to a previous value of 14.9 eV [3]. The valence-band density of states was calculated using DFT-LDA, with the revised pd-repulsion for the self-interaction corrections included. Good agreement between the experimental and theoretical valence-band density of states was obtained. Previous such studies of InN were hampered by the difficulty in preparing InN free surfaces. Conventional methods of surface preparation are severely limited for InN. Here atomic hydrogen cleaning (AHC) cycles were used, which have been shown to successfully prepare clean, electronic-damage free InN surfaces [4]. A combination of core-level XPS, scanning electron microscopy and atomic force microscopy confirmed that AHC produced clean, flat, featureless surfaces.

[1] F. Bechstedt, J. Furthmüller, J. Cryst. Growth 246, 315 (2002)

[2] I. Mahboob et al., Phys. Rev. B 69, 201307(R) (2004)

[3] Q. X. Guo et al., Phys. Rev. B 58, 15304 (1998)

[4] L. F. J. Piper et al., J. Vac. Sci. Technol.A, in press (2005)

Related papers
  1. In-vacancies in Si-doped InN
  2. Parameter-free calculations of electronic properties and optical transitions of MgO, ZnO, and CdO
  3. Irradiation-induced defects in InN and GaN studied with positron annihilation
  4. Surface and bulk electronic properties of significantly cation-anion mismatched oxide semiconductors
  5. Interface, bulk and surface electronic properties of InN
  6. Time-resolved differential transmission and photoluminescence studies of recombination mechanisms in Mg-doped InN 
  7. Electrical and optical properties of Mg-doped InN
  8. Spectral properties of InN and related compounds from first principles
  9. Influence of Doping and Co-doping on the Optical and Electronic Properties of Si Nanocrystallites
  10. Compositional modulation in the InxGa1-xN layers; relation to their optical properties
  11. Recombination processes with and without momentum conservation in degenerate InN
  12. Growth and properties of InN, InGaN, and InN/InGaN quantum wells
  13. Conduction band anisotropy of InN and GaN studied by synchrotron ellipsometry
  14. Surface band bending at n-type and p-type InN by Auger Electron Spectroscopy
  15. Acceptor states in photluminescence of n-InN
  16. Band Structure and Properties of InN and In-rich In1-xGaxN Alloys
  17. Quantized Electron Accumulation, Inversion Layers and Fermi Level-Stabilization in Indium Nitride
  18. Dielectric function of InN: Nonparabolicity and excitonic effects
  19. InN explained within chemical trends
  20. Resonant tunneling and intersubband absorption in AlN-GaN-superlattices

Presentation: oral at E-MRS Fall Meeting 2005, Symposium A, by Louis F. J. Piper
See On-line Journal of E-MRS Fall Meeting 2005

Submitted: 2005-05-05 10:30
Revised:   2009-06-07 00:44
© 1998-2018 pielaszek research, all rights reserved Powered by the Conference Engine