1、Designation: E2735 14Standard Guide forSelection of Calibrations Needed for X-ray PhotoelectronSpectroscopy (XPS) Experiments1This standard is issued under the fixed designation E2735; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision
2、, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide describes an approach to enable users andanalysts to determine the calibrations and standards
3、 useful toobtain meaningful surface chemistry data with X-ray photo-electron spectroscopy (XPS) and to optimize the instrument forspecific analysis objectives and data collection time.1.2 This guide offers an organized collection of informationor a series of options and does not recommend a specific
4、 courseof action. This guide cannot replace education or experienceand should be used in conjunction with professional judgment.Not all aspects of this guide will be applicable in all circum-stances.1.3 The values stated in SI units are to be regarded asstandard. No other units of measurement are in
5、cluded in thisstandard.1.4 This standard is not intended to represent or replace thestandard of care by which the adequacy of a given professionalservice must be judged, nor should this document be appliedwithout consideration of a projects many unique aspects. Theword “Standard” in the title of thi
6、s document means only thatthe document has been approved through the ASTM consensusprocess.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practi
7、ces and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E995 Guide for Background Subtraction Techniques in Au-ger Electron Spectroscopy and X-Ray PhotoelectronSpectroscopyE996 Practice for Reporting Data in Auger Electron Spec-troscopy
8、and X-ray Photoelectron SpectroscopyE1078 Guide for Specimen Preparation and Mounting inSurface AnalysisE1127 Guide for Depth Profiling in Auger Electron Spec-troscopyE1217 Practice for Determination of the Specimen AreaContributing to the Detected Signal in Auger ElectronSpectrometers and Some X-Ra
9、y Photoelectron Spectrom-etersE1523 Guide to Charge Control and Charge ReferencingTechniques in X-Ray Photoelectron SpectroscopyE1577 Guide for Reporting of Ion Beam Parameters Used inSurface AnalysisE1634 Guide for Performing Sputter Crater Depth Measure-mentsE1636 Practice for Analytically Describ
10、ing Depth-Profileand Linescan-Profile Data by an Extended Logistic Func-tionE1829 Guide for Handling Specimens Prior to SurfaceAnalysisE2108 Practice for Calibration of the Electron Binding-Energy Scale of an X-Ray Photoelectron Spectrometer2.2 ISO Standards:3ISO 10810 Surface Chemical AnalysisDepth
11、 ProfilingMeasurement of Sputtered DepthISO 14606 Surface Chemical AnalysisSputter DepthProfilingOptimisation Using Layered Systems as Ref-erence MaterialsISO 14701 Surface Chemical AnalysisX-ray Photoelec-tron SpectroscopyMeasurement of Silicon Oxide Thick-nessISO 14976 Surface Chemical AnalysisDat
12、a Transfer For-matISO 15470 Surface Chemical AnalysisX-ray Photoelec-tron SpectroscopyDescription of Selected InstrumentalPerformance Parameters1This guide is under the jurisdiction of ASTM Committee E42 on SurfaceAnalysis and is the direct responsibility of Subcommittee E42.03 on Auger ElectronSpec
13、troscopy and X-Ray Photoelectron Spectroscopy.Current edition approved Feb. 1, 2014. Published February 2014. Originallyapproved in 2013. Last previous edition approved in 2013 as E273513. DOI:10.1520/E2735-14.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Custo
14、mer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.Copyright ASTM Internati
15、onal, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1ISO 15472 Surface Chemical AnalysisX-ray Photoelec-tron SpectrometersCalibration of Energy ScalesISO/TR 15969 Surface Chemical AnalysisDepthProfilingMeasurement of Sputtered DepthISO 18115-1 Surface Chemical An
16、alysisVocabularyPart 1: General Terms and Terms Used in SpectroscopyISO 18115-2 Surface Chemical AnalysisVocabularyPart 2: Terms Used in Scanning-Probe MicroscopyISO 18116 Surface Chemical AnalysisGuidelines forPreparation and Mounting of Specimens for AnalysisISO 18117 Surface Chemical AnalysisHand
17、ling of Speci-mens Prior to AnalysisISO 18118 Surface Chemical AnalysisAuger ElectronSpectroscopy and X-ray Photoelectron SpectroscopyGuide to the Use of Experimentally Determined RelativeSensitivity Factors for the Quantitative Analysis of Ho-mogeneous MaterialsISO/TR 18392 Surface Chemical Analysi
18、sX-ray Photo-electron SpectroscopyProcedures for DeterminingBackgroundsISO 18516 Surface Chemical AnalysisAuger ElectronSpectroscopy and X-ray Photoelectron SpectroscopyDetermination of Lateral ResolutionISO 19318 Surface Chemical AnalysisX-ray Photoelec-tron SpectroscopyReporting of Methods Used fo
19、rCharge Control and Charge CorrectionISO/TR 19319 Surface Chemical AnalysisAuger ElectronSpectroscopy and X-ray Photoelectron SpectroscopyDetermination of Lateral Resolution, Analysis Area andSample Area Viewed by the AnalyserISO 20903 Surface Chemical AnalysisAuger ElectronSpectroscopy and X-ray Ph
20、otoelectron SpectroscopyMethods Used to Determine Peak Intensities and Infor-mation Required when Reporting ResultsISO 21270 Surface Chemical AnalysisX-ray Photoelec-tron and Auger Electron SpectrometersLinearity ofIntensity ScaleISO 22335 Surface Chemical AnalysisDepth ProfilingMeasurement of Sputt
21、ering Rate: Mesh-Replica MethodUsing a Mechanical Stylus ProfilometerISO 24237 Surface Chemical AnalysisX-ray Photoelec-tron SpectroscopyRepeatability and Constancy of In-tensity Scale3. Terminology3.1 DefinitionsFor definitions of surface analysis termsused in this guide, see ISO 18115-1 and ISO 18
22、115-2.4. Significance and Use4.1 The purpose of this guide is assist users and analysts inselecting the standardization procedures relevant to a definedXPS experiment. These experiments may be based, forexample, upon material failure analysis, the determination ofsurface chemistry of a solid, or the
23、 composition profile of a thinfilm or coating. A series of options will be summarized givingthe standards that are related to specific information require-ments. ISO 15470 and ISO 10810 also aid XPS users inexperiment design for typical samples. ASTM Committee E42and ISO TC201 are in a continuous pr
24、ocess of updating andadding standards and guides. It is recommended to refer to theASTM and ISO websites for a current list of standards.5. Procedure5.1 General Sample Characterization:5.1.1 Sample HistoryThe analyst should obtain a sum-mary of the background information of the sample, includingdesc
25、riptors, history, sample cleaning and handling, existingapplication data, bulk composition, and any prior analysis thathas been conducted. The sample history, especially handling,packing and storage, can impact the approach needed to obtainthe desired information. Because inadequate sample collectio
26、ncan sometimes destroy or minimize the ability to collect thedesired information, it is often necessary to identify the neededinformation and establish the procedures to be used (5.2)before the surface analysis is performed.5.1.2 Vacuum CompatibilityThe compatibility of samplewith instrument vacuum
27、should be considered. Although somesamples have inappropriately high vapor pressures for ambienttemperature operation, some instruments may include a samplecooling stage, which allows these types of materials to beanalyzed. Additionally, newer XPS systems often have im-proved vacuum pumps coupled wi
28、th monochromatic X-raysources (that do not heat the sample) and a small X-ray spotsize (requiring less sample for analysis). As a result, stronglyoutgassing or subliming samples can often be examined.5.2 Design of Experiment:5.2.1 The goal of the experiment should be defined. Experi-mental goals may
29、 include data relating to the surface chemicalcomposition and chemical state, surface segregation,quantification, layer thickness, nanostructures, and so forth.The identification of the specific analysis objectives influencessample handling, instrument setup, the approach to datacollection, and fina
30、lly the methods of data analysis.5.2.1.1 Table 1 is a summary of possible experiments alongwith different calibrations required to obtain meaningful dataor to optimize the instrument for the best data in the timeavailable.4Also included are the ASTM and ISO standards forchecking the parameter. In th
31、e table, an X indicates applica-tions where a calibration is required. Additionally, the calibra-tions are ranked with X = generally important and XX =generally very important calibrations for a given task.5.2.2 General System CheckThe analyst should perform ageneral system health check (including m
32、echanicalcomponents, sample holders, vacuum level, and performancecheck) as recommended by the instrument manufacturer. Manyanalysts have also developed their own methods to verify thegeneral operational health of an instrument. This might bedone, for example, by testing a specimen commonly analyzed
33、by the instrument to quickly verify the binding energies of fewphotoelectron peaks and overall count rates. Based upon theexperiment to be performed, the relative importance of theparameters in Table 1 should be assessed, including calibrationof the binding-energy scale, intensity repeatability and4
34、Castle, J. E., Powell, C. J., Report on the 34th IUVSTA Workshop, XPS: FromSpectra to ResultsTowards an Expert System, Surface and Interface Analysis,Vol26, 2004, pp. 225237.E2735 142constancy, intensity/energy response function (IERF), linearitytest of the intensity scale, energy resolution for the
35、 desiredintensity, lateral resolution, charge compensation, depthresolution, and depth profile rate calibration.5.2.3 Sample Transport and PreparationAs a surfaceanalysis technique, X-ray photoelectron spectroscopy (XPS) issensitive to the outermost few atomic layers of the samplebeing characterized
36、. Specimens should be transported to theanalyst in a container that does not come into direct contactwith the surface of interest. In most cases, the analysis will beperformed on the as-received specimen; therefore, the goalmust be to preserve the state of the surface so that the analysisremains rep
37、resentative of the original surface. Care must thenbe taken to ensure that no outside agents come in contact withthe surface to be investigated. These agents include: fingers,solvents or cleaning solutions, gases (including compressedair) or vapors, metals, tissue or other wrapping materials, tape,c
38、loth, tools, packing materials or the walls of containers.Handling of the surface to be analyzed should be eliminated orminimized whenever possible.5.2.3.1 Proper preparation and mounting of specimens isparticularly critical for surface analysis. Improper preparationof specimens can result in altera
39、tion of the surface compositionand unreliable data. In addition, specimen mounting techniqueshave the potential to affect the intended analysis. Guides E1078and E1829 and/or ISO 18116 and ISO 18117 describe methodsthe surface analyst may need to minimize the effects ofspecimen preparation when using
40、 any surface-sensitive ana-lytical technique. Also described are methods to mount speci-mens so as to ensure that the desired information is notcompromised. Because of the wide range of types of specimensand desired information, only broad guidelines and generalexamples are included in the standards
41、. The optimum handlingprocedures will be dependent on the particular specimen andthe needed information. It is recommended that the specimensupplier consult the surface analyst as soon as possible withTABLE 1 Recommended XPS Calibrations for Defined ExperimentsNOTE 1The X indicates applications wher
42、e a calibration is required. X = generally important, XX = generally very important. Local methodsAareprocedures developed by an individual laboratory or the instrument manufacturer. NPL software for the calibration of the intensity scales of XPSinstruments is available from the UK National Physical
43、 Laboratory.BBCR 261Cis a certified reference tantalum oxide/tantalum foil calibration sampleand NIST SRM 2135cDis a certified nickel/chromium thin-film depth profile standard.InstrumentCalibrationsand ChecksASTMStandardISOStandardAdditionalSourcesElementalCompositionChemicalStateLow LevelDetectionQ
44、uantifi-cationLayerThicknessNano-structuresGeneral System Check Local Method XX XX XX XX XX XXSample Preparation E1829E10781811618117XXXXXXBinding Energy E2108E15231547219318XX XX X XIntensity Repeatabilityand Constancy24237 X X XX XX X XIntensity/EnergyResponse FunctionNPLSoftwareXX X XXLinearity o
45、f IntensityScale2127018118XX XXXPeak Intensities E995 1839220903Local Method X X XX X X XIon Gun and SputterRateE1577E1127E163415969223351460614701BCR 261 XX XXDepth Resolution E1577E1127E1634E163614606 BCR 261NIST SRM2135cXX XXAnalysis Area E1217 19319 X X X XXLateral Resolution 18516 X X X XData R
46、eporting E996 14979 X X X X X XAManual from the system manufacturer.BNational Physical Laboratory (NPL),http:/www.npl.co.uk/science-technology/surface-and-nanoanalysis/services/calibration-software-and-reference-materials-for-electron-spectrometers.CEuropean Institute for Reference Materials and Mea
47、surements, BCR261, certified reference material.DNational Institute of Standards and Technology, NIST-SRM 2135c Ni/Cr Thin Film Depth Profile Standard, http:/www.nist.gov.E2735 143regard to specimen history, the specific problem to be solved orinformation needed, and the particular specimen preparat
48、ion orhandling procedures required.5.2.4 Binding Energy, Energy Scale Linearity, and ChargeCompensationCalibrations of the binding energy (BE) scalesof XPS instruments are required for four principal reasons.First, meaningful comparison of BE measurements from two ormore XPS instruments requires tha
49、t the BE scales becalibrated, often with an uncertainty of about 0.1 to 0.2 eV.Second, identification of chemical state is based on measure-ment of chemical shifts of photoelectron and Auger-electronfeatures, again with an uncertainty of typically about 0.1 to0.2 eV; individual measurements, therefore, should be madeand literature sources need to be available with comparable orbetter accuracies. Third, the availability of databases of mea-sured BEs for reliable identification of elements and determi-nation of chemical states by comp
