This paper presents a study of the optical properties of thermally oxidized nanoporous silicon in the wavenumber range 5000–400 cm<sup>−1</sup>. It is shown for the first time that thermally oxidized nanoporous silicon has two broad regions of reduced transmittance in the wavenumber range from 3720 to 3000 cm<sup>−1</sup> and five narrow zones that have their minima at the following wave numbers: 2920, 2240, 1680, 840, and 600 cm<sup>−1</sup>. The transmittance spectra of the thermally oxidized SiO<sub>2</sub>–Si structure are measured in the wavenumber range 5000–400 cm<sup>−1</sup>. It is established that the thermally oxidized SiO<sub>2</sub>–Si structure is transparent in the wavenumber range 5000–1200 cm<sup>−1</sup> and has narrow absorption peaks insignificant in magnitude at 1090 cm<sup>−1</sup> and 620 cm<sup>−1</sup>. It is shown that thermally oxidized nanoporous silicon can be used as a selectively absorbing and recording medium in the IR range.
© 2012 OSA
Original Manuscript: August 4, 2011
Published: February 29, 2012
A. V. Mikhaĭlov, L. V. Grigor’ev, and P. P. Konorov, "Selective absorption in thermally oxidized nanoporous silicon," J. Opt. Technol. 79, 99-101 (2012)