Premium
Spectral decomposition of R aman spectra of mixed‐phase TiO 2 thin films on Si and silicate substrates
Author(s) -
Schipporeit Sebastian,
Mergel Dieter
Publication year - 2018
Publication title -
journal of raman spectroscopy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.748
H-Index - 110
eISSN - 1097-4555
pISSN - 0377-0486
DOI - 10.1002/jrs.5369
Subject(s) - raman spectroscopy , thin film , materials science , amorphous solid , anatase , substrate (aquarium) , phase (matter) , rutile , luminescence , spectral line , wafer , raman scattering , analytical chemistry (journal) , mineralogy , chemical engineering , optics , nanotechnology , optoelectronics , chemistry , photocatalysis , crystallography , physics , organic chemistry , oceanography , engineering , astronomy , geology , catalysis
We present a method to fit Raman spectra of TiO 2 thin films on silicon wafers, fused silica, and crown glass with adjustable model spectra of the different components of the substrate and the thin film. With reasonable restrictions of the fitting parameters, the method developed in this paper allows a simultaneous fit to the measured spectra. The TiO 2 thin film spectrum is split into one spectrum for the amorphous phase and spectra for each crystalline phase (anatase, rutile, and brookite) being divided into first‐order scattering and a phase background (including second‐order scattering). Moreover, if the substrate is luminescent, the substrate spectrum is split into luminescence and Raman spectra. All decisions on parameters are made by the fitting procedure within a simultaneous fit of a series of spectral models to the observed Raman spectrum. The main strategies for preparing such models are pointed out in a way that they should be applicable to other materials. TiO 2 is a promising and flexible material for photocatalytic applications with rapidly growing interest in mixed‐phase TiO 2 as nanostructured material or thin film. For the analysis of such films, it is important to differentiate the signals of the various phases and to distinguish between signals from the substrate and the film. This provides a means to improve the quantitative evaluation of Raman spectra.