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Ba 1-x Sm 1-x SnO 3 (BSSO, x = 0.00, 0.02, 0.04, 0.06, 0.08, 0.10 and 0.15) thin films were epitaxially grown on (001) oriented MgO substrates by pulsed laser deposition (PLD) technique. The structure analysis was performed by x-ray diffraction (XRD), including 2theta-omega (2θ-ω) scans, omega (ω) scans, phi (φ) scans, and reciprocal space mapping (RSM). Hall effect measurement shows that the lowest room temperature resistivity value can reach to 7.842 mΩ cm in the 0.04 Sm-doped thin film, while the carrier mobility ( μ ) decreases systematically with increasing Sm doping content. Temperature dependent resistivity behavior indicates that the BSSO films exhibit metal-semiconductor transition in the temperature range of 10–300 K with the doping content up to x = 0.08. Optical transmission spectra measurement shows that all the BSSO films exhibit a high transmittance of more than 80% in the visible range. The increasing of optical band gap E g with the increase of Sm doping content was interpreted by the Burstein-Moss effect and the occurrence of octahedral tilt distorting. Excellent optical and electrical properties mean that the BSSO films have potential applications as transparent and conducting oxide (TCO) material. [ABSTRACT FROM AUTHOR]

Transparent and conductive Ta doped BaSnO 3 (BaSn 1−x Ta x O 3 , BSTO) films with x = 0–0.15 were epitaxially grown on MgO single crystalline substrates by a pulsed laser deposition method. The effects of Ta ions incorporation on the microstructure, electrical and optical properties of BSTO films were investigated. X-ray diffraction measurements indicate that the out-of-plane lattice parameters increase gradually with Ta concentration increasing, and the films are relaxed due to the large lattice mismatch between the films and substrate. Atomic force microscopy images reveal that all the films have smooth surface and low roughness. X-ray photoelectron spectra of BSTO films confirm that the Ta ions are presented in the +5 state. The lowest room-temperature resistivity and the highest carrier concentration and Hall mobility were observed in BSTO film at x = 0.07, with the values of 2.525 mΩcm, 5.024 × 10 20 cm −3 , and 4.921 cm 2 /Vs, respectively. Temperature dependent resistivity behavior shows that the BSTO films with low doping content exhibit metal-semiconductor transition at low temperature. The optical transmittances of all BSTO films are more than 80% in the visible region. The optical band gaps were found to increase from 3.52 to 4.23 eV with the increase of Ta doping content and can be attributed to the Burstein-Moss effect. Thus, the superior electrical and optical properties of Ta doped BaSnO 3 films are comparable to that of La and Sb doped BaSnO 3 films, and have potential applications in the optoelectronic devices. [ABSTRACT FROM AUTHOR]

(Ba 1-x Gd x )SnO 3 (BGSO) (x = 0–0.15) films were epitaxially grown on MgO substrates by pulsed laser deposition. Structure analysis was performed using X-ray diffraction, atomic force microscopy, and X-ray photoelectron spectroscopy. Transport properties were investigated by Hall effect and temperature dependent resistivity measurement. Results show that the film resistivity decreases systematically with increasing Gd doping concentration. The lowest room-temperature resistivity of 6.18 mΩcm was observed in film at x = 0.07, with the metal-insulator transition at 30 K, which was attributed to the formation of a degenerate band in films. Optical transmission spectra measurement shows that all the BGSO films have high transmittance of more than 80% in the visible range. The band gap variation with the Gd doping concentration was interpreted by the Burstein-Moss effect. Excellent optical and electrical properties suggest that BGSO films have potential applications in the optoelectronic devices as transparent and conducting oxide material. [ABSTRACT FROM AUTHOR]