Assessment of non-uniform thin films using spectroscopic ellipsometry and imaging spectroscopic reflectometry

• Published in: Thin solid films 2014-11, Vol.571, p.573-578
• Main Authors: Nečas, David, Ohlídal, Ivan, Franta, Daniel, Čudek, Vladimír, Ohlídal, Miloslav, Vodák, Jiří, Sládková, Lucia, Zajíčková, Lenka, Eliáš, Marek, Vižďa, František
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Consistency; Constants; Ellipsometry; Exact sciences and technology; Imaging; Imaging spectroscopic reflectometry; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Mapping; Mapping spectroscopic ellipsometry; Non-uniform thin films; Optical constants: refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity; Optical instruments, equipment and techniques; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of bulk materials and thin films; Optical properties of specific thin films; Physics; Polarimeters and ellipsometers; Reflectometry; Spectroscopic analysis; Spectroscopy; Thin films; Variable-angle spectroscopic ellipsometry
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2013.12.036

Standard variable-angle spectroscopic ellipsometry, mapping spectroscopic ellipsometry with microspot and imaging spectroscopic reflectometry are applied to optical characterisation of a thin SiOxCyHz film considerably non-uniform in thickness and which is also suspected of non-uniformity also in the optical constants. It is shown that using the combination of these three optical methods, enables us to determine the spectral dependencies of the optical constants of the film together with parameters characterising the shape of thickness non-uniformity and fine map of local thickness. The mapping spectroscopic ellipsometry with microspot enables deciding whether the film is non-uniform in optical constants. For the thin film studied it is found that the non-uniformity in optical constants is under experimental accuracy. The consistency of results obtained using individual techniques is checked and the advantages and disadvantages of the techniques are discussed. •Spectroellipsometry is applied to characterisation of considerably non-uniform films.•Auxiliary imaging spectroscopic reflectometry is used to find a fine thickness map.•The techniques utilised enabled to determine the optical parameters of the films.•Comparison of the techniques used is performed.