The XPS Library uses Binding Energy Scale Calibration with Cu (2p 3/2) BE = 932.62 eV and Au (4f 7/2) BE = 83.98 eV.(N*number) identifies the number of NIST BEs that were averaged to produce the BE in the middle column.Mn (2p 3/2 ) Chemical State BEs from: “The XPS Library Spectra-Base”Īnd C (1s) BE = 284.8 eV for NIST BEs Element When using the electron flood gun, the instrument operator should adjust the voltage and the XY position of the electron flood gun to produce peaks from a strong XPS signal (eg O (1s) or C (1s) having the most narrow FWHM and the lowest experimentally measured BE.Native oxides that still show the pure metal can suffer differential charging that causes the C (1s) and the O (1s) and the Metal Oxide BE to be larger.Other BEs can be as low as 284.2 eV or as high as 285.3 eV Depending on your preference or training, the C (1s) BE assigned to this hydrocarbon peak varies from 284.8 to 285.0 eV.The hydrocarbon peak is normally the largest peak at the lowest BE.Normally, to correct for this flood gun induced shift, the BE of the hydrocarbon C (1s) peak maximum from adventitious carbon is used to correct for the charge induced shift. When an electron flood gun is used, the BE scale will usually shift to lower BE values by 0.01 to 5.0 eV depending on your voltage setting.Charge referencing is a common method, but it can produce results that are less reliable.Charge Referencing Methods for Insulators.Floating all samples (conductive, semi-conductive, and non-conductive) and always using the electron flood gun is considered to produce more reliable BEs and is recommended.Samples that behave as true insulators normally require the use of a charge neutralizer (electron flood gun with or without Ar+ ions) so that the measured chemical state spectra can be produced without peak-shape distortions or sloping tails on the low BE side of the peak envelop.This variation increases significantly above 600 eV BE.This range causes BEs in the higher BE end to be larger than expected.Some authors still adjust their energy scale so Cu (2p3/2) appears at 932.2 eV or 932.8 eV because this is what the maker taught them.For various reasons authors still use older energy scale calibrations.Worldwide Differences in Energy Scale Calibrations.The accuracy depends on when the authors last checked or adjusted their energy scale to produce the expected calibration BEs.Different authors use different BEs for the C (1s) BE of the hydrocarbons found in adventitious carbon that appears on all materials and samples.Cu (2p3) BE can vary from 932.2 to 932.8 eV for old publications The accuracy depends on the calibration BEs used to calibrate the energy scale of the instrument.Notes of Caution when using Published BEs and BE Tables from Insulators and Conductors: Six (6) Chemical State Tables of Mn (2p) BEs Manganese Minerals, Gemstones, and Chemical Compounds Overlay of Mn o metal and MnO 2 – Mn (2p) Native Oxide C (1s) = 285.0 (Flood gun OFF) Survey Spectrum of Manganese Dioxide (MnO 2)Ĭaution: BEs from Grounded Native Oxides can be Misleading if Flood Gun is ON Overlay of Mn o metal and Mn Native-Oxide – Mn (2p) Survey Spectrum of Manganese Native Oxide Mn (KLL) Auger Peaks from MnO 2 – chip – conductive Mn Native-Oxide & Manganese Dioxide, MnO 2 Mn (2p) – Extended Range Spectrum – Vertically ZoomedĬan form when ion etched Reactive Metal Surfaces capture Valence Band Spectrum from Manganese, Mn o Metalįresh exposed bulk produced by extensive Ar+ ion etchingįresh exposed bulk produced by extensive Ar+ ion etching Mn (2p) – Extended Range Spectrum *Scofield Cross-Section (σ) for C (1s) = 1.0 Σ: abbreviation for the term Scofield Photoionization Cross-Section which are used with IMFP and TF to generate RSFs and atom% quantitation Spin-Orbit Term, BE (eV) Value, and Scofield σ for Aluminum K α X-rays (1486 eV, 8.33 Ang) Overlaps With Peaks Integrated, Assigned and Labelled Survey Spectrum of Manganese (Mn o ) Metal Study of UHV Gas Capture after Cleaning.Flood Gun Effects on Native Oxide Spectra.Peak-fits and Overlays of Mn Chemical Compounds.IMFP and Cross-sections for Pure Element.→ Periodic Table – HomePage XPS Database of Polymers → Six (6) BE Tables Published literature references, and website links are summarized at the end of the advanced section. The Advanced XPS Information Section is a collection of additional spectra, overlays of spectra, peak-fit advice, data collection guidance, material info,Ĭommon contaminants, degradation during analysis, auto-oxidation, gas capture study, valence band spectra, Auger spectra, and more. The Basic XPS Information Section provides fundamental XPS spectra, BE values, FWHM values, BE tables, overlays of key spectra, histograms and a table of XPS parameters.
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