(XPS)-2 - Washington State University

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Peak Widths and IntensitiesPeak widths: it is a convolution of the natural width of the core level, the width ofthe x-ray line and the analyzer resolution:ΔE=222( ΔE+ ΔE+ ΔEnpa)1/ 2Intensities: Only the ratio of area of lines has some meaning (relative concentration).[ A]σ bζbλbηbIa=[ B] σ aζaλaηaIbσ: cross-section; ζ: fraction of PE events (w/o intrinsic plasmon excitation); λ:mean free path; η: KE dependent spectrometer transmission and I : area of the line
Quantitative Analysis1. Use of standards:I xis the amplitude of the element X in your sample,I x,stdis the amplitude of the element X in pure materialThe concentration of X in your sample is THEN given by C x = I x / I x,stdPROBLEM with this approach is that you need a large No of Standards.2. Modify Method:It introduces the relative sensitivity factor, S xbased upon one pure elementstandard (usually Ag, silver standard). So, if we want to calculate S x:sensitivity for element X from a compound X aY bwe could do it by using:Sx=( A+ B)AIIxAg(pure)
Page 5 and 6: Six features seen in a typical XPS
Page 7 and 8: F 1s peakSharp Peak (core level)O 1
Page 9 and 10: Vacancy created by photoionization
Page 11 and 12: Shake-up satellites: distinct peaks
Page 13 and 14: Auger featuresAuger electron emissi
Page 15 and 16: x 10 3Oxidized surfaces12Cr 2p ---d
Page 17 and 18: Chemical BondingThe curve fitting o
Page 19 and 20: Intensity ratio is given by (2j - +
Page 21: Static Charging (cont.)Auger: Sampl
Page 26 and 27: Quantitative Analysis (cont.)Sx=( A

(XPS)-2 - Washington State University

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