Updating MultiPak

1. Updating MultiPak

2. Whats New In MultiPak Version 9

3. What’s New in MultiPak Version 9 • Current released version 9.2.05 • Release notes located in “ReadMe” file that accompanies a new software version • Contains a list of: • New features • Bug fixes • Known issues • Helpful Hints

4. What’s New in MultiPak Version 9 • New features for XPS data reduction • Improved user interface appearance • Spectral Deconvolution function • Save massaged data function • Zoom function for curve-fit display • PCA smoothing for XPS maps • Image enhance function • Smooth • Sharpen • Background adjustment

5. Spectral Deconvolution Reference Files • Ag 3d5/2 reference files are required to use the spectral deconvolutionsoftware • Instructions for collecting reference files are in the MultiPak manual • Look under “spectral deconvolution” • The reference (calibration) files are stored in the EnergyResolution folder: • C:\MultiPak\Calibration\EnergyResolution • File naming conventions: • AgCal_xx_yy.spe • xx is the instrument type • QT for Quantera • QM for Quantum • VP for VersaProbe • 5k for 5100-5800 • yy is the integer value for the spot size • For example 100, 20, etc • LA for high power mode in version 9.2 and later • HP for high power mode in versions 9.0 and 9.1

6. System Constants File • The system constants file: syscnstn.phi contains user settings • This file can be backed up to backup your personal settings • If the system constants file is corrupted you may not be able to start MultiPak • The solution to this problem is to delete the file and restart MultiPak • Go to C:\Multipak\V9.0\Userdata\Phiuser1\Dr_sys • Select and delete the file: syscnstn.phi

7. MultiPak Manual Tutorial and Data Files

8. MultiPak XPS Handbook Data Files

9. Quantification

10. Quantification • MultiPak uses the following building blocks to calculate atomic concentrations: • A standardized set of relative sensitivity factors based on PHI’s library of empirical RSF data. • Algorithms to model the transmission function of the spectrometer. • X-ray source angle corrections for geometric asymmetry effects. • Key information including transmission function parameters and instrument configuration are stored with data files

11. Relative Sensitivity Factors • Original RSF data published in Surface and Interface Analysis, Volume 3, Number 5, in 1981 • Empirical Atomic Sensitivity Factors for Quantitative Analysis by Electron Spectroscopy for Chemical Analysis • C. D. Wagner, L. E. Davis, M.V. Zeller, J.A. Taylor, R.H. Gale, and L.H. Gale • At a later date the transmission function of the instruments used to create the data was mathematically removed and a “standard” set of sensitivity factors was created

12. Transmission Function Modeling • The transmission function (T) depends generally on kinetic energy (E) and pass energy (Ep). • The transmission function represented by the product of the pass energy and a transmission factor (t) which depends on the retard ratio (R or E/Ep). • The transmission at a specific energy T(E) = Ep x t(R).

13. Transmission Function Modeling t(R) • t(R) for PHI’s spectrometers can be modeled using the equation: A/Ep = [a2/(a2 + R2)]b • where ‘a’ and ‘b’ are constants that are adjusted to model t(R), A is peak area, Ep is pass energy, and R is the retard ratio or E/Ep. • to determine the constants ‘a’ and ‘b’ for the spectrometer, Cu 2p, LMM, and 3p peaks are collected at several pass energies. The normalized peak areas A/Ep are plotted versus retard ratio and the equation A/Ep = [a2/(a2 + R2)]b is applied to the data with a linear least squares fit.

14. Transmission Function Modeling Normalized Peak Areas vs. Retard Ratio Kinetic Energy / Pass Energy Area Ep

15. Transmission Function Modeling Model for t(R) Area Ep Kinetic Energy / Pass Energy a = 24.5 b = 0.207 Linear least squares fit of data to: A/Ep = [a2/(a2 + R2)]b

16. X-ray Source Angle Corrections • The angle between the incident x-ray beam and the input lens of the spectrometer has an effect on photoabsorption and the resulting photoemission process, which effects the sensitivity of a specific atomic orbital. • The correction factor (F) for geometric asymmetry is: F = [1 - .25b(3COS2q-1)] / 4p • where b = the asymmetry parameter for a specific atomic orbital and q = is the angle between the incident x-ray beam and the spectrometer input lens. This is 45 ° for the standard configuration of current PHI XPS instruments.

17. Applying the Corrections • The concentration for a specific element is determined using the equation: Atom % = [(Ix/Sx)/(åIi/Si)]x100 where Ix is intensity or peak area and Sx is the “actual” sensitivity factor for the element. • The “actual” sensitivity factor for each element (Sx) is the product of the “standard” sensitivity factor, the transmission function correction (T(E)), and the asymmetry correction (F). • In MultiPak Fis defined as Fx / Fs, where Fx is the asymmetry correction for transition X and Fs is the asymmetry correction for an “s” orbital

18. Results • This method allows data of mixed pass energies to be used in a quantitative measurement. • This method allows MultiPak to account for changes in instrument geometry and to support data from multiple x-ray sources on the same instrument. • Factors that limit accuracy include: • Signal to noise ratio of the data • Accuracy of background subtraction methods • Accuracy of the “standard” sensitivity factors • Matrix effects • Accuracy of geometric asymmetry corrections