Abstract

The nature of the grazing angle reflection spectrum of the thin oxide layer formed on the surface of aluminum was examined by Kramers-Kronig calculations. It was confirmed that the 960-cm⁻¹ peak seen in the grazing angle reflection spectrum corresponds to the absorption band at 738 cm⁻¹ of a low-temperature transition alumina such as γ-Al₂O₃. The large frequency shift toward higher frequencies is explained in terms of the product between the real and imaginary parts of the refractive index of the oxide. Simulation using the Kramers-Kronig calculation showed, in addition, a very weak structure at about 700 cm⁻¹ in the grazing angle reflection spectrum, which was attributed to a peak shifted from the 590-cm⁻¹ absorption peak of γ-Al₂O₃.

Kramers-Kronig Analysis of Ratio Reflectance Spectra Measured at an Oblique Angle

Marvin R. Querry and Wayne E. Holland
Appl. Opt. 13(3) 595-598 (1974)

Kramers-Kronig Analysis of Relative Reflectance Spectra Measured at an Oblique Angle

George M. Hale, Wayne E. Holland, and Marvin R. Querry
Appl. Opt. 12(1) 48-51 (1973)

Kramers–Kronig analysis of infrared reflection spectra with perpendicular polarization

Kiyoshi Yamamoto, Akio Masui, and Hatsuo Ishida
Appl. Opt. 33(27) 6285-6293 (1994)

Kramers-Kronig Analysis of Reflectance Measured at Oblique Incidence

Dwight W. Berreman
Appl. Opt. 6(9) 1519-1521 (1967)

Validity of the Kramers-Kronig transformation used in reflection spectroscopy

Ralph H. Young
J. Opt. Soc. Am. 67(4) 520-523 (1977)