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Abstract: Pulsed laser deposition was used to prepare amorphous thin films from (GeSe2)100−x(Sb2Se3)x system (x = 0, 5, 10, 20, 30, 40, 50, and 60). From a wide variety of chalcogenide glass‐forming systems, Ge–Sb–Se one, especially in thin films form, already proved to offer a great potential for photonic devices such as chemical sensors. This system has a large glass‐forming region which gives the possibility to adjust the chemical composition of the glasses according to required physical characteristics. The chemical composition of fabricated thin films was analyzed via X‐ray photoelectron spectroscopy (XPS) and compared to energy dispersive spectroscopy (EDS) data. The results of both techniques agree well: a small deficiency in chalcogen element and an excess of antimony was found. The structure of as‐deposited thin films has been investigated by XPS. The presence of the two main structural units, [GeSe4] and [SbSe3] proposed by Raman scattering spectroscopy data analysis, was confirmed by XPS. Moreover, XPS core level spectra analysis revealed the presence of M–M bonds (M = Ge, Sb) in (Ge,Sb)–Ge–(Se)3 and (Ge,Sb)–Sb–(Se)2 entities that could correspond to Ge‐based tetrahedra and Sb‐based pyramids where one of its Se atoms at corners is substituted by Ge or Sb ones. The content of depicted M–M bonds tends to increase with introduction of antimony in the amorphous network of as‐deposited thin films from x = 0 to x = 40 and then it decreases. XPS analysis of as‐deposited thin films shows also the presence of the (Ge,Sb)–Se–(Ge,Sb) and Se–Se–(Ge,Sb) entities. [ABSTRACT FROM AUTHOR]

Thin films of amorphous alumina were fabricated using pulsed laser deposition. Topography, structural, and optical properties of alumina films were investigated depending on process parameters, specifically deposition time under vacuum and partial pressure of argon. Deposited films present good uniformity with RMS roughness ranging from 0.35 to 2.50 nm. Alumina films with thickness lower than 40 nm deposited under vacuum present a non-negligible void content that induces a decrease of the effective refractive index of the layers. Furthermore, introduction of argon gas (at 5×10 −4 and 5×10 −2 mbar) during the deposition process induces grainy structure of the thin films documented by an increase of RMS roughness from 0.35 to 1.5 nm. A decrease of the alumina layers' refractive index is observed in the 300–7500 nm spectral range when increasing Ar pressure. [ABSTRACT FROM AUTHOR]