Silicon oxycarbide formation on SiC surfaces and at the SiC/SiO2 interface

Abstract

Amorphous and single-crystal α-SiC were exposed to various oxygen sources at room temperature. The oxygen sources included the residual gas in an ultrahigh vacuum environment, ambient air, ozone, and oxygen plasma. X-ray photoelectron spectroscopy (XPS) was used to follow changes in the surface composition and to determine the local bonding environment of the Si atoms. It was found that silicon oxycarbide species are formed when these SiC materials are initially exposed to oxygen. With extended exposure to ambient air, a SiO2 layer is subsequently formed over the silicon oxycarbide. However, the native oxide on the single-crystal SiC consists mainly of silicon oxycarbide species. The thicknesses of these native oxides were calculated using the XPS data.

Oxidation behaviour of SiC/SiC ceramic matrix composites in air

“…10. The binding energies used to identify the SiC and SiO 2 are according to standards established by Onneby and Pantano [19], where they defined specific energy level of Si (102.5 eV), SiC (99.5-100.1 eV) and SiO 2 (102.5-102.9 eV). After 1 h oxidation at 1400 • C a clear shoulder is seen on the high energy side (102.5 eV) from the SiC substrate (99.5-100.1 eV) confirming the formation of an oxidation product of SiO 2 (102.5-102.9 eV).…”

Accelerated Degradation Behavior and Cytocompatibility of Pure Iron Treated with Sandblasting

“…3a). 32 The spectra of C 1s (as shown in Fig. 3b) of F320 and F80 samples also show the peak at 282.5 eV which can be assigned to SiC.…”

Influence of surface properties of ceramic particles on their incorporation into cobalt electroless deposits

“…However, it has to be noted that the powder of technical purity (98-99%) was used. The presence of carbon contaminations can favor the formation of the carboxylic groups, while the oxidation of the silicon-containing surface gives silica layer and other intermediate products [20]. About 60% of functional groups revealed on the SiC surface are basic in character.…”

“…They can create during oxidation of the SiC powder, particularly contaminated by carbon [20,21]. For alumina and silica it is assumed that two types of OH groups (acidic and basic) can exist on the oxides surfaces [22].…”