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Lithium niobate is a material of special interest for its challenging functional properties, which can suit various applications. However, high quality 200‐mm LixNb1‐xO3 thin film grown on sapphire substrate have never been reported so far which limits these potential applications. This paper reports the efficient optimization of high quality LiNbO3 thin film deposition on sapphire (001) substrate through chemical beam vapor deposition in a combinatorial configuration. With this technique, flow ratio of Li/Nb can be tuned from ≈0.25 to ≈2.45 on a single wafer. Various complementary characterizations (by means of diffraction, microscopy and spectroscopy techniques) have been performed at different areas of the film (different cationic ratios) in order to investigate the impact of the cationic stoichiometry deviation on the film properties. Close to cationic stoichiometry (LiNbO3), the epitaxial films are of high quality (single phase in spite of two in‐plane domains, low mosaicity of 0.04°, low surface roughness, refractive index and band gap close to bulk values). Deviating from the stoichiometry conditions, secondary phases are detected (LiNb3O8 for Nb‐rich flow ratios, and Li3NbO4 with partial amorphization for Li‐rich flow ratios). LiNbO3 films are of high interest for various key applications in data communications among others. [ABSTRACT FROM AUTHOR]

Perovskite oxide type materials exhibit a great profusion of unique functional properties and for this reason they have been named inorganic chameleon. Nevertheless, their actual applications require the availability of these systems in thin‐film form synthesized through a simple, scalable, and straightforward technique. Metal‐organic chemical vapor deposition (MOCVD) has been shown to be an outstanding process to prepare thin films of multi‐component oxides. Herein, the focus is devoted to oxide perovskite thin films on both single crystal and non‐single crystal substrates through MOCVD processes. This study discusses the principles and the basic rules governing conventional, plasma‐enhanced, and liquid‐assisted MOCVD processes. Among a plethora of oxide perovskites, several classes of functionalities belonging to the perovskite class: from superconductors to dielectrics and giant‐k dielectrics, from colossal magnetoresistance to ionic conductors, piezoelectrics and ferroelectrics, are explored in detail. [ABSTRACT FROM AUTHOR]

Block copolymer (BCP) lithography is one of the most technologically intriguing and scientifically interesting strategies for achieving nanometer‐sized features. This method usually exploits toluene as solvent for the deposition of BCPs in all the processing steps. However, this chemical has some technical disadvantages, such as high toxicity and hygroscopicity. The first aspect can limit its use on the industrial scale because of the protocols on the environmental and operator risks, while the second causes aging effects that can alter the results. In order to overcome these intrinsic limitations, a BCP self‐assembly (BCP‐SA) strategy is presented by using alternative deposition solvents in place of toluene. A preliminary study, based on the physical characteristics, such as volatility, polarity, and hygroscopicity, is carried out to explore two new alternative solvents, ethyl acetate and tetrahydrofuran. The effects on the BCP‐SA due to the new solvents are studied by SEM analysis supported by suitable software for the images elaboration. The results achieved show very promising outcomes for the polymer solutions obtained with ethyl acetate, in terms of uniformity of geometrical features, ordered areas extension, and homogeneity of the pattern obtained, making this chemical a good alternative to toluene. [ABSTRACT FROM AUTHOR]