The reaction of energetic O2+, thermal O2, and thermal O2/ar+ on graphite and the use of graphite for oxygen collector probes

Chemical sputtering of carbon films by argon ions and molecular oxygen at cryogenic temperatures

“…Surprisingly, the yield increases toward lower temperatures in the whole investigated range from 415 to 113 K. Additionally, the yields at the higher ion energy are higher, which can be ascribed to the more effective damage production. The existence of the ion/O 2 synergism in the erosion of carbon materials was proven earlier by Vietzke et al [27], who investigated graphite erosion under 5 keV Ar + ion bombardment in a background of thermal oxygen. A quadrupole mass spectrometer was used to detect the released species and showed CO production in the whole investigated temperature range between 300 and 1500 K. In an analogous fashion to our experiments, the CO signal increased with decreasing temperature between 800 and 300 K. The difference in the temperature below which the increase is observed might be due to the different sample materials, a-C:H and graphite, respectively.…”

Sputtering yield measurements during low energy xenon plasma bombardment

“…The chemical erosion yield of high-energy oxygen ions on carbon, in this temperature regime, is approximately 0.4 due to the formation of volatile CO molecules. 21 This would lead to an estimated weight loss yield, due to chemical erosion, of 0.0004 due to the base pressure in PISCES-B. The weight loss expected from chemical erosion by residual oxygen is within the error of the weight loss measurement at 50 eV for carbon, and clearly much less than the carbon yield measured by weight loss at 100 and 150 eV.…”

A comparison between physically and chemically driven etching in the oxidation of graphite surfaces

“…As a particularly relevant type of surface modification of carbon materials, we concentrate here on oxidation. Oxidation of carbon materials is a topic of scientific and technological relevance [6,[8][9][10][11][12][13], and can be carried out through a variety of approaches. Thus, carbon surfaces can be oxidized via high temperature treatment under air or molecular oxygen [9,14], through oxygen ion bombardment [15][16][17][18], by exposure to oxygen-containing plasmas [10,11,19,20] or ozone [21,22], or by wet chemical and electrochemical means [23].…”