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A simple and direct synthesis method was used to grow silicon carbide nanofibers in CH4/H2 mixture on silicon substrates covered by Fe thin film catalyst using microwave plasma assisted chemical vapour deposition. The silicon source is the substrate itself. The samples have been characterized by field emission scanning electron microscopy and transmission electron microscopy combined with electron energy-dispersive X-ray spectroscopy. These characterizations revealed that fibrous nanostructures having stacking faults planes perpendicular to the growth direction coexist with fibrous with no stacking fault. These two types have a core–shell structure, with a diameter of 25–65 nm, and were both assigned to β-SiC. Selected area electron diffraction pattern shows that the faulted SiC structures exhibit streaks indicating defects (irregular layers) while the other ones have a single crystal pattern. One can also observe that the SiC nanofibers grow along (111) orientation. The formation of SiC nanofibers can be explained by the diffusion of Fe in the silicon substrate due to the high temperature during the process which is around 900 °C. The combination of the etching of the surface by atomic hydrogen and the interaction with carbon radicals and carbon atoms allows then the growth of SiC nanofibers.

AlN thin films are of continued interest for exciting acoustic waves for surface and bulk acoustic wave devices. This work reports on the growth and the characterisation of AlN films with the c-axis inclined. These films are of significant interest for shear wave generation in view of realisation of surface acoustic wave devices operating as liquid sensors. AlN films were deposited on 3inch silicon wafers, covered by a SiO2 buffer layer. The deposition was carried out using an RF magnetron sputtering planar system under various deposition parameters, including pressure and temperature. The crystalline orientation and the inclination of the c-axis of the obtained AlN films were investigated using X-ray diffraction and by scanning electronic microscopy. These analyses showed that a c-axis inclination of up to 13° was obtained in our planar charging system under high pressure and at a temperature of 300°C. The shear mode acoustic wave device based on the deposited c-axis inclined AlN film was produced and showed that a phase velocity of 5832m/s was obtained. This value of shear velocity is discussed.