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In this study, as cost effective and an environmentally friendly lm deposition technology, Atmospheric Solution Precursor Plasma Spray (ASPPS) was utilized for the deposition of the photo-catalytic titanium oxide (TiO 2) lm for the fabrication process of photovoltaic devices for rural electri cation in developing countries. In addition, ethanol-diluted titanium tetra-iso-butoxide (TTIB: Ti(OC 4 H 9) 4) was used as a feedstock. N 2-dominant Ar/N 2 was also utilized as plasma working gas as well as for the elevation of the thermal plasma energy. By controlling deposition distances and temperature, using vortex generation anode nozzle operated at 1 kW, photo-catalytic TiO 2 lm was deposited and its crystallinity was con rmed by X-ray diffraction. Besides, the photo-catalytic properties of the lm were con rmed by the methylene blue decolorization and the surface wettability tests. Surface morphologies of the TiO 2 lm was evaluated using optical micrographs. Furthermore, the lm thickness and strength were measured using micro screw gauge and pencil scratch tester respectively. Lastly, when this Photo-catalytic TiO 2 lm was applied to photovoltaic devices, the device generated an open circuit voltage of 146.7 mV with solar irradiance intensity of 574 W/m 2. From these results it was con rmed that, the ASPPS technology equipped with high cooling ef ciency vortex anode nozzle is available for deposition of TiO 2 lm for the fabrication process of low-cost photovoltaic devices for rural areas in developing countries.

GaN films are grown directly on AlN templates/sapphire substrates without using low‐temperature (LT) buffer layers by metalorganic chemical vapor deposition. AlN templates are complimentarily deformed at the initial growth of GaN, adjusting the a‐lattice constant and tilting crystal orientation slightly. Compared with the film on sapphire substrates using an LT buffer layer, the GaN on the AlN template forms a smoother surface and has better crystalline quality after a shorter growth time at a lower temperature. Higher‐quality InGaN films on the GaN/AlN template are subsequently grown to optimize the thickness exhibiting the minimum Urbach energy which is evaluated by photothermal deflection spectroscopy. A high‐quality AlGaN/InGaN heterostructure is fabricated in which the Shubnikov–de Haas oscillation can be clearly observed from the electron gas of the InGaN channel at the interface.