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The temperature- and frequency-dependent electrical properties of SiO2/3C–SiC/6H–SiC structures have been studied. Capacitance measurements indicate that the single-domain 3C–SiC film is doped with an average concentration of 8.4×1016 cm-3. One nitrogen donor level and a shallow donor level were found. The measured interface state density near the conduction band edge of 3C–SiC is below 1011 cm-2 eV-1 and increases towards mid-gap as obtained from conductance and capacitance measurements. Our results are consistent with the assumption that the interfaces of SiO2/n-type SiC consist of two different kinds of interface traps.

Inorganic scintillating fibers have a large potential as highly granular detector components in hadron and particle physics as well as in medical applications. With the micropulling-down-method a fast and cost efficient technique was developed over the last decades to grow such fibers from the melt. This paper will present the recent development of the quality of LuAG:Ce and LYSO:Ce fibers in terms of light output and light attenuation inside the fiber. For this purpose different steps in optimizing the fiber growth will be compared with the achieved fiber performance. In addition the response of the fibers to low energetic gamma rays will be studied and different readout concepts for the fibers will be discussed and compared.

Batch-fabricated SiC nanowires were heated under an ammoniac flow up to 1400 °C. The ensuing product was characterized by SEM, HRTEM, EDX and XRD. As we found, SiC nanowires were completely converted into faceted α-Si3N4 nanorods with diameters ranging from 10 to 500 nm and lengths lower than 10 µm. These nanorods present hexagonal cross sections. We suggest a growth mechanism based on the progressive elimination of carbon through hydrogenation reactions and the growth of silicon nitride nanorods via the high-temperature nitridation of silicon.

We have studied the effect of the deposition temperature and high temperature annealing on the quality of thin GaN and AlN layers on 6H-SiC substrates. By systematic characterization using reflection high electron energy diffraction (RHEED) and atomic force microscopy (AFM), we have shown that the two nitrides act differently in the early stage of growth. GaN undergoes a Stransky-Krastanov transition enhanced by the post growth annealing. AlN is less sensitive to the effect of annealing and the layers are comparatively smoother than the GaN ones. GaN gives easily the cubic phase at low temperatures whereas it is less feasible for AlN. For each material, better morphology and crystallinity are achieved at the highest temperature studied (800°C) but AlN is preferable to GaN as no islands are formed with AlN.