Many strategies have been developed for the synthesis of silicon carbide (SiC) thin films on silicon (Si) substrates by plasma-based deposition techniques, especially plasma enhanced chemical vapor deposition (PECVD) and magnetron sputtering, due to the importance of these materials for microelectronics and related fields. A drawback is the large lattice mismatch between SiC and Si. The insertion of an aluminum nitride (AlN) intermediate layer between them has been shown useful to overcome this problem.
View Article and Find Full Text PDFThis article reports the design, construction, and first use of an experimental device consisting of a specially designed vacuum chamber equipped with a reactive sputtering magnetron (RSM) to be used for controlled deposition of thin films on a Si(100) flat substrate. The setup was designed to allow for in situ and real-time recordings of X-ray diffraction patterns during the growth of the deposited films and was installed in the X-ray diffraction and spectroscopy beamline emerging from a superconducting wiggler source at the Brazilian Synchrotron Light Laboratory. The first use of the RSM setup was an in situ and real-time X-ray diffraction study of processes of growth of multilayered aluminum nitride thin films, whereas the operation parameters of the reactor were sequentially changed.
View Article and Find Full Text PDFIn this work, we report development of hybrid nanostructures of metal nanoparticles (NP) and carbon nanostructures with strong potential for catalysis, sensing, and energy applications. First, the etched silicon wafer substrates were passivated for subsequent electrochemical (EC) processing through grafting of nitro phenyl groups using para-nitrobenzene diazonium (PNBT). The X-ray photoelectron spectroscope (XPS) and atomic force microscope (AFM) studies confirmed presence of few layers.
View Article and Find Full Text PDFHierarchical carbon nanostructures based on ultra-long carbon nanofibers (CNF) decorated with carbon nanotubes (CNT) have been prepared using plasma processes. The nickel/carbon composite nanofibers, used as a support for the growth of CNT, were deposited on nanopatterned silicon substrate by a hybrid plasma process, combining magnetron sputtering and plasma-enhanced chemical vapor deposition (PECVD). Transmission electron microscopy revealed the presence of spherical nanoparticles randomly dispersed within the carbon nanofibers.
View Article and Find Full Text PDFIEEE Trans Ultrason Ferroelectr Freq Control
August 2010
We present a theoretical calculation and experimental results for a waveguiding layer acoustic wave (WLAW). The experimental device is modeled by the finite element method (FEM) for the AlN/ZnO/diamond structure. It was found that the AlN thickness must be at least larger than 3lambda/2 to obtain negligible surface displacement.
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