Papers by Keyword: Carbonization Process

Abstract: Utilization of palm oil waste in palm kernel shells as activated carbon, the activated carbon manufacturing goes through several processes, including dehydration, carbonization, and activation. Palm shell particle size was controlled during the activated carbon synthesis process through the temperature of the milling time and carbonization processes. The carbonization process was carried out using an electric furnace at carbonization temperatures 400, 600, and 800 °C, respectively. A carbonization time was 1 hour under vacuum condition to produce initial values of particle and grain sizes that had a neat structure and had absorption capacity. The particle size of formed activated carbon was measured by PSA (particle size analyzer) type Coulter LS 100Q micron scale. The particle size of active carbon was dependent on the carbonization temperature at 400, 600, and 800 °C was obtained particle size 19,90, 9,507, and 6,264 μm, respectively. Several characterizations are required to determine the properties of activated carbon was obtained. FTIR Spectrophotometer was used to observe activated carbon’s molecule structure before and after dehydration and carbonization process. It was found that the specific fingerprint at 2913,91 cm^-1 and 2923,56 cm^-1 for the carbon chain of activated carbon. Other physical and chemical properties were conducted to investigate moisture content, thermal property, yield enhancement, and formed product appearance.

Abstract: 3C-SiC/Si heteroepitaxy is hampered by large mismatches in lattice parameters (19.7%) and thermal expansion coefficient (8%) leading to 3C-SiC films containing high defects density. To reduce the presence of defects, a multi-step growth process in a CVD reactor is used. The aim of the work is to study the effect of carbonization on differently oriented Si surfaces, experiencing a 200°C-wide temperature range in a CVD reactor, to improve the crystalline quality. TEM analysis are carried out to evaluate thickness, crystal orientations and defects of carbonized layers with respect to the time-dependence of the process and to the different orientations of the Si substrate. It will be shown that process-related defects are strictly correlated to the substrate orientation either for size, density, occupied area, shape or thickness. Uniform, flat and crystalline thin SiC films are obtained with a low defect density.

Abstract: An approach for the defect density reduction in 3C-SiC epitaxially grown on Si is to improve the quality of the carbonized layer during the early stage of growth. For this reason the conventional carbonization process was replaced by a slower and nearer equilibrium carbonization method. Carbon is introduced by implantation into oxide of an oxidized Si substrate, near the SiO2/Si interface, and then it is transferred to the Si surface by annealing. Good quality 3C-SiC grains are formed embedded into the Si substrate, which are absolutely flat at the SiO2/Si interface. Another advantage of the new carbonization process is the elimination of the cavities due to the suppression of Si out-diffusion.