Polarized reflectance spectroscopy and spectroscopic ellipsometry determination of the optical anisotropy of gallium nitride on sapphire

Guolin Yu, Hiroyasu Ishikawa, Takashi Egawa, Tetsuo Soga, Junji Watanabe, Takashi Jimbo, Masayoshi Umeno

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The refractive indices n (E⊥c) and n (E ∥ c) of the hexagonal GaN on sapphire substrates have been determined in the transparent region using the polarized reflection measurements. It is found that the difference in the refractive indices for E⊥c and E ∥ c is below 3% over the entire wavelength range measured, and ∈ the high-frequency dielectric constant, is 5.14 for E⊥c and 5.31 for E ∥ c. Ellipsometry angles, Δ and ψ, have been calculated using the results of n, n and the thickness of the film, and an excellent agreement has been obtained between the calculated results and ellipsometric measured data.

Original languageEnglish
Pages (from-to)L1029-L1031
JournalJapanese Journal of Applied Physics, Part 2: Letters
Issue number8 PART A
Publication statusPublished - 1997 Aug 1



  • GaN
  • Optical anisotropy
  • Refractive index
  • Spectroscopic ellipsometry

ASJC Scopus subject areas

  • Engineering(all)
  • Physics and Astronomy (miscellaneous)
  • Physics and Astronomy(all)

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