Differences in Auger electron spectroscopy and x-ray photoelectron spectroscopy results on the bonding states of oxygen with β-SiC(100) surfaces

Abstract

Auger electron spectroscopy (AES) and x-ray photoelectron spectroscopy (XPS) measurements have been carried out on the β-SiC(100) surface simultaneously. The AES and XPS results differ significantly in the bonding state of oxygen for both as-grown surfaces and as-etched surfaces. Differences in the same carbon-KLL Auger spectra induced by both electron beams and x rays from the same surface suggest that the electron beam used in AES removed considerable amounts of carbonaceous species in the contaminant layers. Furthermore, comparison of the Si 2p and Si LVV spectra revealed that the SiOx (x<2) species on the surface was also reduced by the electron beam used in AES. Although previous AES results have shown that both as-grown and as-etched surfaces of β-SiC(100) were covered with only submonolayer coverage of oxygen bonded to Si atoms, with no detectable carbonaceous contaminants, this work shows that the real surfaces, however, are covered with several tens of contaminant layers, including SiO, CC, CH, and CO bonds.

Microstructure and microhardness of SiC nanoparticles reinforced magnesium composites fabricated by ultrasonic method

“…However, the Si2p of AZ91D/5SiC spectra consisted of three peaks at 99 eV, 100.3 eV, and 102.8 eV. These were identified as those due to Si, SiC, SiO 2 , respectively [24][25][26][27][28]. C 1s spectra of AZ91D show the one peak 284.5 eV that is primarily hydrocarbon, a common contaminant.…”

X-ray spectroscopy of the oxidation of 6H-SiC(0001)

“…Several groups, using x-ray photoelectron or spectroscopy ͑XPS͒ or Auger electron spectroscopy mea-surements, observe the formation of complex carbon and suboxide-rich interfaces during the oxidation of ␣ or ␤-SiC. [4][5][6] Hornetz, Michel, and Halbritter 7 suggest that the C-rich interface layer is formed by a Si 4 C 4Ϫx O 2 compound involving sp 2 bonds between carbon atoms. This statement is followed by Afanasev et al 8 who interpret their internal photoemission measurements as the evidence of the possible formation of such an interfacial C-rich cluster layer and try to explain the different oxidation rates of the two polar ␣-SiC surfaces.…”

Influence of Surface Cleaning and Calcination on Rheological Properties of Silicon Carbide Aqueous Suspensions

“…The peak around 283 eV is because of SiC, whereas the peak around 285 eV is because of extraneous carbon, 21 which has been attributed to either a hydrocarbon or a contaminant carbon layer. 22 After calcination at 5501C, the contaminant carbon layer is removed to a great extent and no obvious peaks corresponding to C-C bonds are found at 10001C. It should be mentioned that the maximum sampling depth obtainable using XPS, even under optimum conditions, is only about 10 nm.…”

“…Figure 8(b) shows the C 1s spectra obtained from SiC specimens studied in this work. The peak around 283 eV is because of SiC, whereas the peak around 285 eV is because of extraneous carbon, 21 which has been attributed to either a hydrocarbon or a contaminant carbon layer 22 . After calcination at 550°C, the contaminant carbon layer is removed to a great extent and no obvious peaks corresponding to C–C bonds are found at 1000°C.…”