Thin rare earth (RE) oxide films are emerging materials for microelectronic, nanoelectronic, and spintronic applications. The state-of-the-art of thin film deposition techniques as well as the structural, physical, chemical, and electrical properties of thin RE oxide films and of their interface with semiconducting substrates are discussed. The aim is to identify proper methodologies for the development of RE oxides thin films and to evaluate their effectiveness as innovative materials in different applications.

Thin rare earth (RE) oxide films are emerging materials for microelectronic, nanoelectronic, and spintronic applications. The state-of-the-art of thin film deposition techniques as well as the structural, physical, chemical, and electrical properties of thin RE oxide films and of their interface with semiconducting substrates are discussed. The aim is to identify proper methodologies for the development of RE oxides thin films and to evaluate their effectiveness as innovative materials in different applications.

The thesis concerned the NdNiO3/NdGaO3 thin films with various thicknesses 150 nm, 73 nm and 17 nm. Samples have been obtained by RF - sputtering and post annealing deposition treatment at the 800°C and O2 250 bar, during 48h. The thesis had two mainly goals. First one, identify source responsible for different switching properties of the thin films NdNiO3/NdGaO3 (observed in DC measurements 150 nm abrupt while for 17 nm film vanishing metal - insulator transition). This goal has been achieved thanks XPS studies, i.e., analysis of the valence bands and core level of Ni2p, O1s and Nd3d spectra. The attempt to establish an effect of charge disproportion of nickel ion 2Ni3+ ® Ni3+d + Ni3-d and observed it in experimental phonon spectra across metal - insulator transition have been a second goal of the thesis. These studies have been performed thanks the Raman scattering studies and theoretical lattice dynamics calculation (LADY). This thesis contributed to the general understanding of the metal - insulator transition in RNiO3 perovskite. The XPS and Raman spectroscopy studies appeared as pertinent tools to investigate the properties of rare earth oxides thin films that are also promising for various applications.

Recent studies indicate that China accounts for about 96 percent of the world's supply of rare earth materials (REMs). With REMs becoming increasingly important for a growing number of high-tech applications, appropriate action must be taken to mitigate the effects of a shortage of critical REMs in defense systems and components.Bringing together i