Infrared spectroscopy characterization of 3C–SiC epitaxial layers on silicon

Abstract

We have measured the transmission Fourier transform infrared spectra of cubic silicon carbide (3C–SiC polytype) epitaxial layer with a 20 µm thickness on a 200 µm thick silicon substrate. Spectra were recorded in the 400–4000 cm−1 wavenumber range. A novel approach of IR spectra computations based on the recursion capability of the C programming language is presented on the basis of polarized light propagation in layered media using generalized Fresnel's equations. The complex refractive indices are the only input parameters. A remarkable agreement is found between all of the experimental SiC and Si spectral features and the calculated spectra. A comprehensive assignment of (i) the two fundamental transverse optical (TO) (790 cm−1) and longitudinal optical (LO) (970 cm−1) phonon modes of 3C–SiC, (ii) with their overtones (1522–1627 cm−1) and (iii) the two-phonon optical-acoustical summation bands (1311–1409 cm−1) is achieved on the basis of available literature data. This approach allows sorting out the respective contributions of the Si substrate and SiC upper layer. Such calculations can be applied to any medium, provided that the complex refractive index data are known.

Stacked Layers of Different Porosity in 4H SiC Substrates Applying a Photoelectrochemical Approach

“…The small peaks at 1545 cm −1 and 1625 cm −1 are due to phonon overtones of SiC. 27,28 So, the measurement in transmission mode shows that the detached porous film still consists mainly of SiC. This is in accordance with the SIMS measurement where the C-and Si-signals exceeded the limits of the detector.…”

“…The spectrum of the latter sample shows two characteristic peaks of SiC at 800 cm −1 (TO phonon) and 975 cm −1 (LO phonon). 27,28 The etched sample also shows these peaks together with a main peak at 1030 cm −1 which is attributed to Si-O-Si stretching vibrations. 29 The minor peak at 975 cm −1 can be assigned to Si-F 2 vibrations.…”

Synthesis and characterization of porous bioactiveSiCtissue engineering scaffold

“…FTIR analysis of the SiC powder prior to any surface treatment showed bands at 1,300 and 1,530 cm −1 (Figure 1a) characteristic for Si─C stretching vibration (Indulekha, Thomas, Rajeev, Ninan, & Gouri, 2018; Pluchery & Costantini, 2012). The notable shoulder in the peak centered at 1,620 cm −1 is indicative of a C═O stretch.…”

Infrared spectroscopy of silicon carbide layers synthesized by the substitution of atoms on the surface of single-crystal silicon

“…For single-crystal cubic SiC, these parameters are as follows: ε ∞ = 6.5, ω TO = 796 cm -1 , ω LO = 972 cm -1 , and γ = 4.7 cm -1 [15]. The reflectance spectra were calculated by the recursive method using the Fresnel formulas [8,24]. The calculated spectrum in the wavenumber range from 700 to 1100 cm -1 was fitted to the experimental spectrum by varying the thickness and the phonon damping coefficient of disordered SiC.…”

“…The structure, composition, and a number of properties of SiC films grown by the substitution of atoms have been investigated using different methods [1,2]. However, until recently, SiC layers grown by the substitution of atoms have not been investigated by means of a non-destructive optical characterization method that has been widely used for studying the structure of crystalline silicon carbide [4][5][6][7][8][9][10], namely, infrared spectroscopy. It is well known that, upon the interaction of vibrational modes of SiC with infrared radiation, the spectrum exhibits strong features in the wavenumber range from 750 to 1000 cm -1 .…”