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Abstract: Thin films of La0.85Sr0.15MnO3 (LSM) are deposited on (100) silicon wafer and YSZ (yttria-stabilized zircornia) electrolyte substrates by magnetron sputtering using a single-phase LSM target. The conditions for sputtering are systematically studied, including substrate temperature (from room temperature to 600°C), the argon background pressure (from 1.2×10−2 to 3.0×10−2 mbar), and deposition time. Results show that the optimal conditions for producing a dense, uniform, and crack-free LSM film include a substrate temperature of 600°C and an argon pressure of 1.9×10−2 mbar. Further, a testing cell with a dense LSM film, an YSZ electrolyte membrane, and a porous LSM counter electrode is prepared and the electrochemical properties of the dense LSM film on YSZ substrate are studied. It was found that the thickness, morphology, and microstructure of LSM films critically influence the electrochemical properties. [Copyright &y& Elsevier]

Interface engineering has emerged as a fertile and efficacious approach to turn functional properties in the field of film systems. In this work, the interfacial properties of sputtered yttrium oxide films on zinc sulfide substrate (Y 2 O 3 /ZnS) were analyzed by transmission electron microscopy (TEM), X-ray photoelectron spectrum (XPS) depth profile and nano-scratch measurement. An interface layer with the depth of 20 nm between Y 2 O 3 film and ZnS substrate was directly observed by TEM. Under different film growth conditions, although the interfacial features including interfacial width and composition distribution exhibit similar behavior, it is found that higher cohesive strength is obtained under a special substrate bias voltage of −160 V at low substrate temperature. Such an enhanced mechanical property can be understood by the role of physisorbed oxygen in the interfacial region, in which less physisorbed oxygen with van der Waals bonds leads to a strong adhesion. Our results provide a favorable strategy to achieve strong adhesion between oxide and sulfide at low temperature, which are urgent in future micro-electric applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Highly crystalline In 2 O 3 films are grown by pulsed reactive magnetron sputtering. • Substrate heating further improves the film crystallinity and conductivity. • 400 °C is the limit for benefiting to obtain the optimum crystallinity of In 2 O 3 films. • The films deposited at 400 °C yield the lowest resistivity of 1.28 × 10-4 Ω⋅cm. • An average transmittance of greater than 80% are also obtained at 400 °C. A transparent conductive oxide (TCO) should have a combination of high electrical conductivity and optical transmission property to fulfill the challenging demands of industrial applications. So far, doped TCOs have been mostly considered to fulfill the technological challenges. In this study, we demonstrate that indium oxide (In 2 O 3) thin films without intentional doping can be deposited with high crystallinity under specific film growth conditions leading to thin films with high mobility, high electrical conductivity, and high transmittance. In 2 O 3 thin films have been deposited by reactive pulsed direct current magnetron sputtering (pulsed DCMS) from an indium target on substrates in a temperature range from room temperature (RT) to 600 °C. Detailed investigations on In 2 O 3 thin films are performed and the film properties such as crystallinity, microstructure, chemical bonding states, electrical and optical properties are revealed. Enhanced plasma density and ionization degree provided by the employed reactive pulsed DCMS and the intentional substrate heating during the thin film deposition give possibility to deposit highly crystalline thin films which are preferentially oriented in (2 2 2) direction. The substrate heating enhances the crystallinity of the grown films up to a certain optimum temperature: 400 °C. When the substrate temperature is above 400 °C, the carrier concentration and mobility decrease due to the grain refinement effect caused by growth competition of grains in different orientations. The films grown at 400 °C indicate the presence of high oxygen vacancy concentrations, which can directly be associated with a high charge carrier concentration despite the lack of intentional doping. The undoped In 2 O 3 films in this study grown at 400 °C show highly promising and competitive electrical properties such as low resistivity of 1.28 × 10-4 Ω⋅cm and the high carrier mobility of 69 cm2/Vs. The average transmittance of the In 2 O 3 films with the highest conductivity is found to be greater than 80% in the visible to the near-infrared spectral region owing to an enhancement in the carrier mobility and an optical bandgap in the range from 3.61 eV to 3.77 eV. [ABSTRACT FROM AUTHOR]

Molybdenum doped zinc oxide thin films have been prepared by RF magnetron sputtering. The influence of the film thickness (120–500 nm) on the structural, electrical, and optical properties of the films is investigated respectively. X-ray diffraction (XRD) studies reveal that with an increase in the film thickness, the crystallinity of the film improves. The obtained film with thickness of 500 nm exhibits the best electrical properties with the lowest resistivity of around 9.6 × 10 −4 Ω cm. The mobility varied from 7.8 to 14.7 cm 2 V −1 s −1 without reducing the achieved high carrier concentration of ∼4.5 × 10 20 cm −3 . Optical band gaps extracted from transmission spectra shows irregular changes due to the Burstein–Moss shift modulated by many-body effects. [ABSTRACT FROM AUTHOR]