The infrared optical functions of AlxGa1-xN determined by reflectance spectroscopy

G. Yu, Hiroyasu Ishikawa, M. Umeno, T. Egawa, J. Watanabe, T. Soga, T. Jimbo

Research output: Contribution to journalArticle

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Abstract

Infrared reflectivity measurements have been carried out on samples with structures of GaN/sapphire and AlxGa1-xN/GaN/sapphire as well as sapphire substrates. Analyses of the reflectance data of sapphire using the Kramers-Kronig technique and fitting of the reflectance spectra of GaN and AlxGa1-xN samples using analytical expressions have been made. The high-frequency dielectric constant ε and the transverse phonon frequency ωTO, are found to vary from 5.15 to 4.2 and from 559.7 to 586.4 cm-1, respectively, when the composition x is varied from 0 to 0.35 at room temperature. The E2 mode, which arises from the disordered state of the alloys, has been observed in the reflectivity spectrum of AlxGa1-xN, and the intensity of the peak is enhanced by increasing the Al content.

Original languageEnglish
Pages (from-to)1472-1474
Number of pages3
JournalApplied Physics Letters
Volume73
Issue number11
DOIs
Publication statusPublished - 1998
Externally publishedYes

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sapphire
reflectance
spectroscopy
permittivity
room temperature

ASJC Scopus subject areas

  • Physics and Astronomy (miscellaneous)

Cite this

The infrared optical functions of AlxGa1-xN determined by reflectance spectroscopy. / Yu, G.; Ishikawa, Hiroyasu; Umeno, M.; Egawa, T.; Watanabe, J.; Soga, T.; Jimbo, T.

In: Applied Physics Letters, Vol. 73, No. 11, 1998, p. 1472-1474.

Research output: Contribution to journalArticle

Yu, G, Ishikawa, H, Umeno, M, Egawa, T, Watanabe, J, Soga, T & Jimbo, T 1998, 'The infrared optical functions of AlxGa1-xN determined by reflectance spectroscopy', Applied Physics Letters, vol. 73, no. 11, pp. 1472-1474. https://doi.org/10.1063/1.122177
Yu, G. ; Ishikawa, Hiroyasu ; Umeno, M. ; Egawa, T. ; Watanabe, J. ; Soga, T. ; Jimbo, T. / The infrared optical functions of AlxGa1-xN determined by reflectance spectroscopy. In: Applied Physics Letters. 1998 ; Vol. 73, No. 11. pp. 1472-1474.
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