Electrical properties of p-NiO films fabricated by RF magnetron sputtering were studied for hydrogen sensor applications. A response of sheet resistance to hydrogen concentration in air has been measured at elevated temperature. Significant changes in sheet resistance of NiO films were observed even for H2 concentration of a few ppm in air. The sensibility of NiO films to hydrogen trace was further increased by Pd clusters deposited on the NiO surface. The best sensibility result achieved on the NiO film was: 0.3 ppm of H2 in air at 145̊C

Epitaxial n-type ZnO film has been grown, on a commercial 5 μm thick p-type 4H-SiC(00.1) Al doped epilayer, by atomic layer deposition. A full width at half maximum of the ZnO 00.2 diffraction peak rocking curve of 0.34°± 0.02° has been measured. Diodes formed on the n-ZnO/p-4H-SiC heterostructure show rectifying behavior with a forward to reverse current ratio at the level of 10⁹ at ±4 V, a leakage current density of ∼6 × 10⁻⁸ A/cm², and a low ideality factor equal to 1.17 ± 0.04. In addition, the diodes exhibit selective photoresponse with a maximum at 367 nm, and with a current increase of ∼10³ under illuminations with respect to the dark value, which makes such devices prospective candidates for ultraviolet light sensors.

Effects of aluminum (Al) and nitrogen (N) implantation performed at room and at elevated (500 °C) temperatures on epitaxial n-type 4H polytype silicon carbide as well as post-implantation annealing have been studied by Raman scattering spectroscopy. The amorphization of 4H–SiC is observed because of ion implantation effects. The Raman analysis showed that the recovery of the crystallinity increased with an increase in the annealing temperature. However, for samples implanted with high doses, the full crystal recovery was not complete even with annealing temperatures up to 1800 °C, and crystal defects were still present in the recrystallized layer, which was confirmed by transmission electron microscopy. Raman scattering spectra were collected at room temperature using a micro-Raman spectrometer. The visible (488 nm) and deep ultraviolet (266 nm) lasers were used as excitation sources. For the DUV laser, the optical penetration depth is less than the implanted layer thickness, and the area near the surface layer can be exactly probed. In contrast, the visible Raman spectrum shows bands characteristic of bulk 4H–SiC, which arise from the underlying non-implanted region. Based on the analysis of the longitudinal optical phonon–plasmon coupled mode, the electrical parameters for ${\text{N}}_2^{+}$ implanted samples were evaluated, where electron concentration n = 3.05 × 10¹⁸ cm⁻³ and mobility μ = 50 cm²/V s, respectively. The results are consistent with the parameters measured by the Hall method.

In this work the electrical properties of Ni and Ni₂Si contacts on n-type 4H-SiC were correlated to the strong structural changes at the contact/SiC interface upon annealing. We can conclude that only δ-Ni₂Si grains play a main role in determining electrical transport properties of the Ni-based ohmic contacts to n-SiC. It is presumed that a recrystallization and texturization of δ-Ni₂Si phase on (0001)SiC-surface during high temperature annealing (> 900°C) contributes to the change of barrier heights, as well as specific contact resistance of contacts.