Radiation damage during surface analysis

X-ray induced reduction of Au and Pt ions on silicon substrates

“…Reduction of metal ions while recording XPS (X-Ray photoelectron spectroscopy) data has been reported and is considered as a nuisance [24][25][26]. However, a recent study reports on the utilization of X-rays and electron beams for inducing in-situ oligomerization reactions [27,28].…”

“…In addition to X-rays, electron, ion, and other energetic particle exposures, which are frequently encountered for cleaning and/or depthprofiling, also cause reduction of certain metal ions to their lower oxidation states [29][30][31][32][33][34]. The extent of reduction varies drastically from one metal ion to another and extensive efforts had been devoted to correlate this with certain chemical/ physical properties of them [24][25][26][27][28][29][30][31][32][33][34]. In one of our earlier work, we had claimed that the extent of X-ray induced reduction could be related with the electrochemical reduction potential of the metal ion [35,36].…”

XPS Investigation of X-Ray-Induced Reduction of Metal Ions

“…2-10 Electron, ion, and other energetic particle exposure, which is frequently utilized for cleaning and/or depth-pro ling, also causes damage, and similar to Xrays, this approach invariably gives rise to the reduction of the m etal ions to lower oxidation states and/or preferential removal of oxygen. 5,[11][12][13][14][15] The extent of reduction, however, varies drastically from one metal ion to another.…”

“…1 A particular kind of damage is the reduction of the m etal ions, which can cause severe interference in cases where determination of the formal oxidation state is important, as is the case in the majority of the applications of XANES, EXAFS, and XPS. [2][3][4][5][6][7][8][9][10] Electron, ion, and other energetic particle exposure, which is frequently utilized for cleaning and/or depth-pro ling, also causes damage, and similar to Xrays, this approach invariably gives rise to the reduction of the m etal ions to lower oxidation states and/or preferential removal of oxygen. 5,[11][12][13][14][15] The extent of reduction, however, varies drastically from one metal ion to another.…”

“…2-10 Electron, ion, and other energetic particle exposure, which is frequently utilized for cleaning and/or depth-pro ling, also causes damage, and similar to Xrays, this approach invariably gives rise to the reduction of the m etal ions to lower oxidation states and/or preferential removal of oxygen. 5,[11][12][13][14][15] The extent of reduction, however, varies drastically from one metal ion to another.In this contribution, we will demonstrate reduction by X-rays of Au, Hg, Bi, V, and W m etal ions during our XPS analysis of various kinds of samples we have carried out over the years. 16,17 We will also discuss the possibility of correlating the ability of the metal ions to undergo Xray-induced reduction with their electrochemical reduction potentials.…”