, Volume 51, Issue 9, pp 1186–1193 | Cite as

Hopping conductivity and dielectric relaxation in Schottky barriers on GaN

  • N. I. Bochkareva
  • V. V. Voronenkov
  • R. I. Gorbunov
  • M. V. Virko
  • V. S. Kogotkov
  • A. A. Leonidov
  • P. N. Vorontsov-Velyaminov
  • I. A. Sheremet
  • Yu. G. ShreterEmail author
Physics of Semiconductor Devices


A study of the current and capacitance dependences on the forward voltage in Au/n-GaN Schottky diodes, the sub-band optical absorption spectra, and the defect photoluminescence in n-GaN bulk crystals and thin layers is reported. It is shown that defect-assisted tunneling is the dominant transport mechanism for forward-biased Schottky contacts on n-GaN. The dependences of the current and capacitance on forward bias reflect the energy spectrum of defects in the band gap of n-GaN: the rise in the density of deep states responsible for yellow photoluminescence in GaN with increasing energy and the steep exponential tail of states with an Urbach energy of E U = 50 meV near the conduction-band edge. A decrease in the frequency of electron hops near the Au/n-GaN interface results in a wide distribution of local dielectric relaxation times and in a dramatic transformation of the electric-field distribution in the space-charge region under forward biases.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    A. Lidow, J. Strydom, M. Rooij, and D. Reusch, GaN Transistors for Efficient Power Conversion (Wiley, Chichester, 2015).Google Scholar
  2. 2.
    Z. Yatabe, J. T. Asubar, and T. Hashizume, J. Phys. D: Appl. Phys. 49, 393001 (2016).CrossRefGoogle Scholar
  3. 3.
    M. E. Levinshtein, S. L. Rumyantsev, R. Gaska, J. W. Yang, and M. S. Shur, Appl. Phys. Lett. 73, 1089 (1998).ADSCrossRefGoogle Scholar
  4. 4.
    L. S. Yu, Q. Z. Liu, Q. J. Xing, D. J. Qiao, S. S. Lau, and J. Redwing, J. Appl. Phys. 84, 2099 (1998).ADSCrossRefGoogle Scholar
  5. 5.
    K. Suzue, S. N. Mohammad, Z. F. Fan, W. Kim, O. Aktas, A. E. Botchkarev, and H. Morkoç, J. Appl. Phys. 80, 4467 (1996).ADSCrossRefGoogle Scholar
  6. 6.
    D. Yan, J. Jiao, J. Ren, G. Yang, and X. Gu, J. Appl. Phys. 114, 144511 (2013).ADSCrossRefGoogle Scholar
  7. 7.
    S. Karmalkar, D. M. Sathaiya, and M. S. Shur, Appl. Phys. Lett. 82, 3976 (2003).ADSCrossRefGoogle Scholar
  8. 8.
    J. Racko, J. Pechácek, M. Mikolášek, P. Benko, A. Grmanová, L. Harmatha, and J. Breza, Radioeng. 21, 213 (2012).Google Scholar
  9. 9.
    S. D. Ganichev, I. N. Yassievich, and V. Prettl, Phys. Solid State 39, 1703 (1997).ADSCrossRefGoogle Scholar
  10. 10.
    E. J. Miller, E. T. Yu, P. Waltereit, and J. S. Speck, Appl. Phys. Lett. 84, 535 (2004).ADSCrossRefGoogle Scholar
  11. 11.
    T. Sawada, Y. Ito, K. Imai, K. Suzuki, H. Tomozawa, and S. Sakai, Appl. Surf. Sci. 159–160, 449 (2000).CrossRefGoogle Scholar
  12. 12.
    N. I. Bochkareva, I. A. Sheremet, and Yu. G. Shreter, Semiconductors 50, 1369 (2016).ADSCrossRefGoogle Scholar
  13. 13.
    V. Voronenkov, N. Bochkareva, R. Gorbunov, P. Latyshev, Y. Lelikov, Y. Rebane, A. Tsyuk, A. Zubrilov, and Y. Shreter, Jpn. J. Appl. Phys. 52, 08JE14 (2013).CrossRefGoogle Scholar
  14. 14.
    F. Ioculano, F. Roccaforte, F. Giannazzo, and V. Raineri, Appl. Phys. Lett. 90, 092119 (2007).ADSCrossRefGoogle Scholar
  15. 15.
    M. Mamor, J. Phys.: Condens. Matter 21, 335802 (2009).Google Scholar
  16. 16.
    T. Mori, T. Kozawa, T. Ohwaki, Y. Taga, S. Nagai, S. Yamasaki, S. Asami, N. Shibata, and M. Koike, Appl. Phys. Lett. 69, 3537 (1996).ADSCrossRefGoogle Scholar
  17. 17.
    M. A. Reshchikov and H. Morkoç, J. Appl. Phys. 97, 061301 (2005).ADSCrossRefGoogle Scholar
  18. 18.
    C. H. Qiu, C. Hoggatt, W. Melton, M. W. Leksono, and J. I. Pankove, Appl. Phys. Lett. 66, 2712 (1995).ADSCrossRefGoogle Scholar
  19. 19.
    O. Ambacher, W. Reiger, P. Ansmann, H. Angerer, T. D. Moustakas, and M. Stutzmann, Solid State Commun. 97, 365 (1996).ADSCrossRefGoogle Scholar
  20. 20.
    L. Balagurov and P. J. Chong, Appl. Phys. Lett. 68, 43 (1996).ADSCrossRefGoogle Scholar
  21. 21.
    P. B. Klein and S. C. Binari, J. Phys.: Condens. Matter 15, R1641 (2003).ADSGoogle Scholar
  22. 22.
    S. M. Sze, Physics of Semiconductor Devices, 2nd ed. (Wiley, New York, 1981).Google Scholar
  23. 23.
    D. Monroe, Phys. Rev. Lett. 54, 146 (1985).ADSCrossRefGoogle Scholar
  24. 24.
    T. Tiedje and A. Rose, Solid State Commun. 37, 49 (1980).ADSCrossRefGoogle Scholar
  25. 25.
    N. I. Bochkareva, Yu. T. Rebane, and Yu. G. Shreter, Semiconductors 49, 1665 (2015).ADSCrossRefGoogle Scholar
  26. 26.
    N. I. Bochkareva, E. A. Zhirnov, A. A. Efremov, Yu. T. Rebane, R. I. Gorbunov, and Yu. G. Shreter, Semiconductors 39, 594 (2005).ADSCrossRefGoogle Scholar
  27. 27.
    N. I. Bochkareva, V. V. Voronenkov, R. I. Gorbunov, F. E. Latyshev, Yu. S. Lelikov, Yu. T. Rebane, A. I. Tsyuk, and Yu. G. Shreter, Semiconductors 47, 127 (2013).ADSCrossRefGoogle Scholar
  28. 28.
    D. V. Lang, J. D. Cohen, and J. P. Harbison, Phys. Rev. B 25, 5285 (1982).ADSCrossRefGoogle Scholar
  29. 29.
    J. D. Cohen and D. V. Lang, Phys. Rev. B 25, 5321 (1982).ADSCrossRefGoogle Scholar
  30. 30.
    D. L. Dexter, Phys. Rev. B 101, 48 (1956).ADSCrossRefGoogle Scholar

Copyright information

© Pleiades Publishing, Ltd. 2017

Authors and Affiliations

  • N. I. Bochkareva
    • 1
  • V. V. Voronenkov
    • 1
  • R. I. Gorbunov
    • 1
  • M. V. Virko
    • 2
  • V. S. Kogotkov
    • 2
  • A. A. Leonidov
    • 2
  • P. N. Vorontsov-Velyaminov
    • 3
  • I. A. Sheremet
    • 4
  • Yu. G. Shreter
    • 1
    Email author
  1. 1.Ioffe InstituteSt. PetersburgRussia
  2. 2.Peter the Great St. Petersburg Polytechnic UniversitySt. PetersburgRussia
  3. 3.St. Petersburg State UniversitySt. PetersburgRussia
  4. 4.Financial University under the Government of the Russian FederationMoscowRussia

Personalised recommendations