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Polycrystalline 3C-SiC films are deposited on SiO2 coated Si substrates by low pressure chemical vapour deposition (LPCVD) with C3H8 and SiH4 as precursors. Controlled nitrogen doping is performed by adding NH3 during SiC growth to obtain the low resistivity 3C-SiC films. X-ray diffraction (XRD) patterns indicate that the deposited films are highly textured (111) orientation. The surface morphology and roughness are determined by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The surface features are spherulitic texture with average grain size of 100 nm, and the rms roughness is 20nm (AFM 5 x 5 mu m images). Polycrystalline 3C-SiC films with highly orientational texture and good surface morphology deposited on SiO2 coated Si substrates could be used to fabricate rf microelectromechanical systems (MEMS) devices such as SiC based filters.

We report on stacking fault (SF) detection in free-standing cubic-SiC epilayer by the Raman measurements. The epilayer with enhanced SFs is heteroepitaxially grown by low pressure chemical vapour deposition on a Si(100) substrate and is released in KOH solution by micromechanical manufacture, on which the Raman measurements are performed in a back scattering geometry. The TO line of the Raman spectra is considerably broadened and distorted. We discuss the influence of SFs on the intensity profiles of TO mode by comparing our experimental data with the simulated results based on the Raman bond polarizability (BP) model in the framework of linear-chain concept. Good agreement with respect to the linewidth and disorder-induced peak shift is found by assuming the mean distance of the SFs to be 11 angstrom in the BP model.

Nano-graphite films have been deposited on n-Si substrates by microwave plasma chemical vapour deposition. The surface morphology and microstructure of the films were tested by scanning electron microscopy, x-ray diffraction and Raman spectroscopy. In the field emission measurement, a turn-on field of 0.5 V/μm and a high emission-site density of 105/cm2 on a tested emission area of (34×35 mm2) have been obtained.

The present study had evaluated the effects of wasted battery liquid on the bone marrow cells, Hepatic and Nephric of toxicity in Kunming mice. The chromosomal aberration (CA) assay were used to evaluate the genotoxic and blood samples were obtained to measure total bilirubin (TBIL), alanine aminotransferase (ALT), aspertate aminotransferase (AST), serum creatinine (Cr) and blood serum uric acid nitrogen (BUN).The results indicated that the mitotic index (MI) were inhabited only statistically significant (p < 0.05) at the 60% concentrations of the dose-level by counting the metaphase cells in bone marrow cells. The frequency of CA cells and aberration cells increased at high concentrations (40% and 60%) of dose-level. The highest frequency of CA cells got to 13.8% on 60% concentration. Compared with the control group, TBIL and ALT were in statistically significant difference (p < 0.05 or P

Epitaxial growth of semiconductor films in multiple-wafer mode is under vigorous development in order to improve yield output to meet the industry increasing demands. Here we report on results of the heteroepitaxial growth of multi-wafer 3C-SiC films on Si(100) substrates by employing a home-made horizontal hot wall low pressure chemical vapour deposition (HWLPCVD) system which was designed to be have a high-throughput, multi-wafer (3x2-inch) capacity. 3C-SiC film properties of the intra-wafer and the wafer-to-wafer including crystalline morphologies, structures and electronics are characterized systematically. The undoped and the moderate NH3 doped n-type 3C-SiC films with specular surface are grown in the HWLPCVD, thereafter uniformities of intra-wafer thickness and sheet resistance of the 3C-SiC films are obtained to be 6%similar to 7% and 6.7%similar to 8%, respectively, and within a run, the deviations of wafer-to-wafer thickness and sheet resistance are less than 1% and 0.8%, respectively.