CasaXPS User’s Manual - University of Saskatchewan

1 CasaXPS User s Manual for Version , October 2001 Product design: Casa Software Ltd. Documentation: Acolyte Science. Manual version CasaXPS and the User s Manual are copyright 2001 Casa Software rights in this document is subject to change without notice and does notrepresent a commitment on the part of the copyright holder. The softwaredescribed in this document is furnished under a license agreement. No partof this publication may be copied, reproduced, stored in a retrieval system,or transmitted in any form or by any means, electronic, mechanical, photoreproduction, recording or otherwise without the prior written consent ofCasa Software Ltd.

2 Acknowledgements CasaXPS wishes to thank all those connected with theproduction of this Manual and the software system it particular, thanks are due to those who provided experimentaldata, results, and interpretations which form the bulk of theexamples here. Notable among these contributors are: MorganAlexander, Graham Beamson, David Briggs, Peter Cumpson,Kevin Harrison, Len Hazel, Fran Jones, Simon Page, RoyPaynter and Martin SeahAll third party Trade Marks are acknowledged and used references to company names in sample output and tem-plates are for demonstration purposes only and are not intendedto imply any endorsement, or refer to any particular existing or-ganisation or equipment.

3 CasaXPS and the User s Manual are copyright 2001 Casa Software Ltd. Contents Introduction .. 5 Getting Started .. 6 Installing CasaXPS .. 6 Starting CasaXPS .. 6 Terminology .. 6A Quick Tour of CasaXPS .. 7 Step 1: Load the experiment file .. 8 Step 2: Select a spectrum for processing .. 8 Step 3: Identify peaks.. 9 Step 4: Annotate peaks using element markers 11 Step 5: Create quantification regions .. 11 Step 6: Adjust region start and end points .. 12 Step 7: Print the results .. 14 Data Display and Browser Windows .. 15 Element Library .. 16 Graph Annotation .. 17 Processing .. 17 Quantification .. 17 ISO 14976 ( VAMAS ) Files .. 17 ISO 14976 File Format.

4 19 Partially Encoded Format Versions .. 19 File Structure .. 20 Experiment header .. 21 Data Blocks .. 21 Binding vs Kinetic Energy .. 22 Experimental Variable .. 22 Transmission Correction and Quantification .. 22 Transmission Functions .. 23 Quantification .. 24 Data Display and Browser .. 25 Understanding the Data .. 25 Selecting the ISO 14976 Blocks .. 26 Zooming the Data .. 26 Tiles of Spectra .. 26 Tile Display .. 27 Colours .. 28 Fonts .. 29 Display Parameters and Scrolled Tiles .. 29 Graph Annotation .. 31 Quantification Tables .. 31 Moving Annotation and the History Mechanism 32 Peak Labels .. 32 Text Annotation .. 33 Processing .. 34 Smoothing.

5 34 Differentiation .. 35 Integration .. 35 Energy Calibration .. 35 Intensity Calibration .. 36 Contents Processing History .. 36 Element Library .. 38 Library File Structure .. 38 Loading an Element Library .. 40 Identifying Peaks .. 41 Quantification .. 42 Regions .. 42 Synthetic Components .. 44 Quantification Calculation .. 45 Quantification Report .. 45 Optimisation of the Peak Parameters .. 47 Propagating Quantification .. 49 Data Editor .. 49 Derivatives and Peak Envelopes .. 50 Quantification by Example .. 51 Report Files and Excel .. 54 Line Shapes and Backgrounds .. 55 A List of Line-Shapes .. 57 Gaussian/Lorentzian Product Form .. 57 Gaussian/Lorentzian Sum Form.

6 57 Alternative Asymmetric Line-Shapes .. 58 Line-Shapes Based upon Backgrounds .. 59 Line-Shapes Available in CasaXPS .. 59 Further adjustments to the basic shapes .. 60 Asymmetric Line-Shapes .. 61 Modifications to the Doniach Sunjic function . 62A New Line-Shape .. 64 Background Subtraction .. 65 Adjusting the universal cross-section .. 68 Simulating Spectra using Tougaard methods .. 69 Using the Calculator and Comparing Spectra .. 71 Creating a Comparison File .. 71 The Calculator .. 72 Principal Component Analysis .. 80 Introduction .. 80 Theory of Principal Component Analysis .. 80 Residual Standard Deviation ( Real Error ) .. 82 Chi square .. 83 Target Factor Analysis.

7 83 Target Testing .. 84 Principal Component Analysis by Example .. 84 Principal Component Analysis and Real Data . 90 PCA and CasaXPS .. 94 Viewing the Data in Factor Space .. 96 Monte Carlo Methods - Uncertainties in Intensity Calculations .. 97 Monte Carlo Data Sets .. 98 Error Matrix .. 98 Contents Monte Carlo: A Simple Example .. 99 Quantification .. 102 Monte Carlo End Point Determination .. 102 Integration Region Limits .. 102 Intensities Determined by Peak-Fitting .. 104 Summary .. 106 Analytical Applications .. 107 Organic Polymers and Curve Fitting .. 107 Quantification using Tagged Regions .. 111 Introduction .. 111 Tagging regions in a survey scan.

8 112 Tagging for different line shapes .. 113 Trend Analysis for Metal Oxidation .. 114 Introduction .. 114 PCA for Aluminium Oxidation Sequence .. 116 Synthetic Model for an Oxidation Sequence . 117 Peak Fit Using Doniach Sunjic Line Shapes . 118 Adjusting a Custom Quantification Report .. 120 Using Different File Formats .. 123 Kratos DS800 Binary Files .. 123VG Eclipse Files .. 124 VGX900 (Ron Unwin) .. 125 Dayta System Files (Bristol IAC system) .. 127 Kratos Vision ASCII files .. 128 SSI M-Probe Files .. 129 PHI MultiPak ASCII files .. 130 Command Summary .. 131 Main menubar .. 131 File .. 131 View .. 132 Window .. 132 Options .. 132 Help .. 133 Toolbar.

9 133 Options Bar .. 134 Processing Dialog windows .. 136 Page Layout .. 136 Tile Display Parameters .. 136 Quantification .. 138 Processing .. 140 Annotation .. 141 Library .. 141 Appendix 1: ISO 14976 format files annotated .. 143 Appendix 2: ISO 14976 and the World Wide Web 148 Appendix 3: Definitions and Formulae.. 149 Glossary of terms .. 149 Formulae: Peak shapes .. 149 Gaussian/Lorentzian Product Form .. 149 Gaussian/Lorentzian Sum Form .. 149 Contents Doniach Sunjic: .. 150 Appendix 4: References and other Resources .. 150 World wide web links: .. 150 References from the Text Footnotes: .. 151 Appendix 5: Quick Reference Card .. 151 5 Introduction CHAPTER 1 Computer Aided Surface Analysis for X-ray Photoelec-tron Spectroscopy ( CasaXPS ) has been designed and writ-ten for analysts and research scientists who use XPS forsurface characterisation.

10 In contrast to the special purpose control systems that formpart of commercial XPS instruments, CasaXPS offers acompact, portable, efficient and user-friendly processingsystem to anyone with an IBM compatible (Pentium) PCrunning Microsoft Windows 95 (or later) or suitable emula-tor. It incorporates much of (in many cases more than) theprocessing functionality of the instrument linked packageswithout recourse to unfamiliar operating systems or hard-ware or proprietary file formats. It is designed from the out-set on the basis of the ISO 14976 Surface Chemical AnalysisStandard Data Transfer Format and so by design has a uni-versal, cross platform approach, independent of anythingother than a reasonable adherence to the ISO standard.