Fabrication of organic emissive thin films by mist deposition method and evaluation of substrate temperature dependence
Mist deposition method has the advantage of low-cost and energy-saving for the fabrication of organic thin films. We fabricated thin films of organic emissive materials, tris (8-hydroxyquinoline) (Alq3) and rhodamine 6G by the mist deposition method using ultrasonic transducer. The thicknesses of them clearly depend on the substrate temperature during the mist deposition by the boiling point of the solvent. The PL spectra clearly demonstrated that the thin films of Alq3 and rhodamine 6G were successfully fabricated.
Heteroepitaxy of Corundum-Structured α-Ga2O3 Thin Films on α-Al2O3 Substrates by Ultrasonic Mist Chemical Vapor Deposition
Ga2O3 thin films of the α-phase, that is, the corundum structure (in the trigonal system), have been epitaxially obtained on sapphire (α-Al2O3) substrates, in contrast to the strong tendency of Ga2O3 to assume a heterogeneous crystal structure, that is, the β-gallia structure (in the monoclinic system) on sapphire. This result is advantageous for high-quality films and is due to the growth by mist chemical vapor deposition (CVD) at low temperatures of 430–470 °C. The α-Ga2O3 films have narrow full-widths at half maximum (FWHMs) in their X-ray diffraction rocking curves, for example, about 60 arcsec. The root mean square (RMS) roughness of the surface was as small as 1 nm. The optical band gap energy obtained was 5.3 eV, and the films were almost completely transparent in the near-ultraviolet and visible regions. The epitaxial growth of α-Ga2O3 films on sapphire is beneficial for the fabrication of oxide optical and electronic devices.
The osprey process: principles and applications
Spray forming in the Osprey mode involves the sequential stages of atomization and droplet consolidation to produce near-net shape preforms. This review traces the history and development of the process with particular reference to the processing science base and attendant metallurgical principles. The process has been scaled up for the fabrication of tubular and billet-shaped products in stainless steels, superalloys, cast irons, tool steels, aluminum alloys, and copper alloys. Alloy development via spray forming has resulted in improved mechanical properties, compared to ingot metallurgy