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Photoluminescence (PL) spectra of Cr doped Ba x Sr 1 - x TiO 3 (x = 0–0.84) (BST) thin films were investigated for the first time. XRD patterns revealed typical peaks of BST microcrystalline perovskite phase. Chromium doping of BST thin films was accompanied by the appearance of PL consisting of rather pronounced lines centered at 1.570–1.600 eV (789.8–774.9 nm) at 12 K, for x = 0–0.84, respectively. These lines are attributed to the zero-phonon transitions 2 E → 4 A 2 of octahedral coordinated Cr 3+ ions in Ti sites of BST. At T ≥ 165 K, the intra ion d - d transitions in Cr 3 + are not significantly influenced by the neighborhood of CrO 6 complexes. [ABSTRACT FROM AUTHOR]

The RF modulated plasma jet system was used for the deposition of Ba x Sr 1- x TiO 3 (BST), and SrTiO 3 (STO) thin films on Si and multi-layer system Si/SiO 2 /TiO 2 /Pt substrates. BSTO and STO thin films were analyzed using X-ray diffraction. During deposition, the substrate was heated at 500°C. Emission spectroscopy of the plasma was used to control the concentration of sputtered particles from the hollow cathode, mainly Sr and Ba atoms. XRD diffraction confirmed the presence of BSTO and STO perovskite phase in the films. The optical band gap obtained from spectroscopic ellipsometry was correlated with composition. [ABSTRACT FROM AUTHOR]