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Indium tin oxide (ITO) thin films were rapid thermal annealed (RTA) for 5 min at a temperature of 550 °C in different exposures of nitrogen gas. Effects of these exposures on the structural, morphological, electrical, and optical properties of these films were investigated using X-ray diffraction, atomic force microscopy and field emission-scanning electron microscopy, four-point probe and hall effect measurements, and ultraviolet-visible-near-infrared (UV-VIS-NIR) spectrophotometer, respectively. The un-exposed RTA ITO films maintained (400) plane preferential orientation similar to the un-annealed sample. However, this plane preferential orientation was reduced relative to (222) plane for exposed RTA sample. The grains and surface roughness parameters were reduced for exposed and enhanced for un-exposed RTA samples as compared to the un-annealed sample. Relatively higher electrical conductivity, average solar transmittance, and bandgap values were observed for ITO films annealed while exposed to nitrogen gas. The exposed RTA ITO films showed sheet resistance of 7.91 Ω sq −1 , average solar transmittance of 83%, and bandgap of 3.93 eV. Findings from this study suggest that RTA exposure have the potential to control ITO thin films properties, hence, extending its potential applications.

We report on the passivation by hydrogen and the subsequent thermal reactivation of the acceptors in Al-doped p-type 6H-SiC. Capacitance-voltage measurements revealed that the near-surface free carrier concentration was reduced by at least an order of magnitude after hydrogen plasma treatment. The thermal stability of the Al-H complex in hydrogenated SiC was investigated through a series of isothermal anneals at temperatures ranging from 200 to 275 °C, while applying a reverse bias to a Ru Schottky barrier. Ru was chosen as the Schottky barrier metal for both its permeability to hydrogen as well as its thermal stability. The electric field associated with the applied reverse bias caused the dissociated hydrogen to drift deeper into the material, thereby confirming the positive charge state of atomic H in p-type SiC. The thermal dissociation of the electrically neutral Al-H complex was found to obey first-order kinetics for temperatures above 225 °C with a dissociation energy of (1.51±0.12) eV.

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