Effects of Metallic, Semiconducting, and Insulating Substrates on the Coupling Involving Radiative Polaritons in Thin Oxide Films

Abstract

Through simulations, this work explores the effects of conducting, semiconducting, and insulating substrates on the absorption of infrared radiation by radiative polaritons in oxide layers with thicknesses that range from 30 nm to 9 μm. Using atomic layer deposition, oxide layers can be formed in the nanometer scale. Our results suggest that the chemistry and conductivity of the substrate determine the amount of absorption by radiative polaritons in oxide layers thinner than the skin depth. The effects of the chemistry and conductivity of the substrate are especially effective for oxide films thinner than about 250 nm, which we label as the substrate sensitive thickness of the oxide film.

Excitation of radiative polaritons by polarized broadband infrared radiation in thin oxide films deposited by atomic layer deposition

“…1 The substrate sensitive thickness is defined in Ref. 2 as the upper limit thickness where the IR radiation interaction with the thin oxide film significantly a) Author to whom correspondence should be addressed; electronic mail: scarelgx@jmu.edu depends on substrate chemistry and conductivity, and was found to be 250 nm. 2 The films were deposited using ALD (Ref.…”

Origin of the low frequency radiation emitted by radiative polaritons excited by infrared radiation in planar La2O3films

“…Beyond 0 θ =70°, the uncertainty of the i ω values increases because of the small percentage of IR beam cross section effectively exploited in the measurements at grazing angles. In IR spectra, all oxides exhibit dips with similar widths [23][24][25][26]36]. Generally, the i ω values in thin oxide films are found in the microwave to low FIR frequency range (10-450 cm -1 ), and are only slightly substrate-dependent.…”

“…Since x k is complex, the direction of propagation of the radiation leaked to the surrounding space is uncertain [17]. [23,36]. The polarization is achieved using a ZnSe polarizer.…”