1、Designation: E1162 11Standard Practice forReporting Sputter Depth Profile Data in Secondary Ion MassSpectrometry (SIMS)1This standard is issued under the fixed designation E1162; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the
2、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 practice covers the information needed to describeand report instrumentation, specimen parameters, experi
3、mentalconditions, and data reduction procedures. SIMS sputter depthprofiles can be obtained using a wide variety of primary beamexcitation conditions, mass analysis, data acquisition, andprocessing techniques (1-4).21.2 LimitationsThis practice is limited to conventionalsputter depth profiles in whi
4、ch information is averaged over theanalyzed area in the plane of the specimen. Ion microprobe ormicroscope techniques permitting lateral spatial resolution ofsecondary ions within the analyzed area, for example, imagedepth profiling, are excluded.1.3 The values stated in SI units are to be regarded
5、asstandard. No other units of measurement are included in thisstandard.1.4 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 practices and determine th
6、e applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:3E673 Terminology Relating to Surface Analysis3. Terminology3.1 For definitions of terms used in this practice, seeTerminology E673.4. Summary of Practice4.1 Experimental conditions and variables that a
7、ffect SIMSsputter depth profiles (1-4) and tabulated raw data (wherefeasible) are reported to facilitate comparisons to other labo-ratories or specimens, and to results of other analytical tech-niques.5. Significance and Use5.1 This practice is used for reporting the experimentalconditions as specif
8、ied in Section 6 in the “Methods” or“Experimental” sections of other publications (subject toeditorial restrictions).5.2 The report would include specific conditions for eachdata set, particularly, if any parameters are changed fordifferent sputter depth profile data sets in a publication. Forexampl
9、e, footnotes of tables or figure captions would be usedto specify differing conditions.6. Information to Be Reported6.1 Instrumentation:6.1.1 If a standard commercial SIMS system is used, specifythe manufacturer and instrument model number and type ofanalyzer, such as, magnetic sector, quadrupole, t
10、ime-of-flight,and so forth. Specify, the model numbers and manufacturer ofany accessory or auxiliary equipment relevant to the depthprofiling study (for example, special specimen stage, primarymass filter, primary ion source, electron flood gun, vacuumpumps, data acquisition system, and source of so
11、ftware, etc.).6.1.2 If a nonstandard commercial SIMS system is used,specify the manufacturer and model numbers of components(for example, primary ion source, mass analyzer, data system,and accessory equipment).6.2 Specimen:6.2.1 Describe the specimen as completely as possible. Forexample, specify it
12、s bulk composition, preanalysis history,physical dimensions. If the specimen contains dopants, forexample, semiconductors, report the dopant type and concen-tration. For multicomponent specimens, state the degree ofspecimen homogeneity. Describe any known contaminants.6.2.2 State the method of mount
13、ing and positioning thespecimen for analysis. Specify any physical treatment of thespecimen mounted in the SIMS analysis chamber (for example,heated, cooled, electron bombarded, and so forth). Note thespecimen potential relative to ground. Describe the method ofspecimen charge compensation used (if
14、any), for example,conductive coatings or grid, electron flooding, etc.1This practice is under the jurisdiction of ASTM Committee E42 on SurfaceAnalysis and is the direct reponsibility of Subcommittee E42.06 on SIMS.Current edition approved Nov. 1, 2011. Published December 2011. Originallyapproved in
15、 1987. Last previous edition approved in 2006 as E1162 06. DOI:10.1520/E1162-11.2The boldface numbers in parentheses refer to the references at the end of thisstandard.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual
16、 Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.3 Experimental Conditions:6.3.1 Primary Ion SourceGive the following paramet
17、erswhenever possible: Composition of beam (if mass filtered, givethe specific ion and isotope, for example,16O); angle ofincidence (relative to the surface normal); ion beam energy;charge state and polarity; current (including the method usedfor measurement, for example, Faraday cup); beam diameter(
18、including the method used for measurement); size and shapeof sputtered area; primary beam current density for a stationarybeam (A/m2); beam raster size and rate (if used); primary iondose rate averaged over the sputtered area (ions/m2s). If theprimary ion beam is pulsed at some point during the prof
19、ile(such as in a time-of-flight SIMS) details of the pulsing shouldbe described (pulse width, repetition rate, extent of beambunching, and so forth). In addition, any special alignment ortuning of the primary column should be specified or refer-enced. State if this is a dual beam or single beam anal
20、ysis. Inthe case of dual beam depth profiling (one continuous and theother pulsed), parameters of both primary ion sources shouldbe described in detail.6.3.2 Secondary Ion Mass SpectrometerGive the follow-ing parameters whenever possible: analyzed area versus totalsputtered area (for example, image
21、field/selected area aperturesize for stigmatic ion microscopes; raster/electronic signalgating for ion microprobes, and so forth); collection angle(angle between surface normal and secondary ion collectionoptics); the spectrometer energy acceptance/bandpass withinthe secondary ion energy distributio
22、n used during depth pro-files (particularly important if energy discrimination is used toremove polyatomic ion interferences); reflectron voltages,pulsing conditions, and post-acceleration voltages for time-of-flight instruments; mass resolution (M/DM where DM is thepeak width at a specified fractio
23、n of the maximum intensity(such as, 50 % or 10 %) for an ion peak of mass M); methodused to perform selected ion monitoring during sputtering (forexample, electrostatic or magnetic peak switching proceduresfor double focusing instruments); the type of specimen chargecompensation used if any (for exa
24、mple, changes in samplepotential biasing during depth profile). If any electron floodgun is employed, specify electron current or dose (electrons /m2).6.3.3 Secondary Ion Intensity MeasurementSpecify thetype of detector (for example, electron multiplier, Faraday cup)and detector bias used including
25、the counting (integration) timeused for each measurement of each ion of interest. For analogdetection, give the detector system time constant. For pulsecounting detection, give the pulse pair resolution includingdead time corrections. For rapidly rastered primary beams,correct intensities (counts/se
26、cond) to instantaneous values bymultiplying by the ratio of total sputtered area to the analyzedarea (important procedure to help assess possible detectorsaturation limitations (5).6.3.4 VacuumSpecify pressures in the primary column,specimen chamber and mass spectrometer prior to and duringsputter d
27、epth profiling, including the type of vacuum pumping.Also give the composition of the residual gas, if available. Ifflooding of the sample surface region or backfilling of theanalysis chamber with reactive gases (for example, oxygen) isused give the details of the procedure including the partialpres
28、sure of the reactive gas.6.4 Quantification by Data Reduction:6.4.1 ConcentrationsIf any elemental concentrations arepresented, state clearly the methodology used for quantification(6 and 7). In addition, specify the details of any external orinternal standards used including methods for normalizati
29、on incomparing ion intensities in reference materials to ion intensi-ties in specimen depth profiles. A commonly used methodmakes use of Relative Sensitivity Factors derived from mea-surements of ion-implanted reference materials to calculateimpurity concentrations in similar matrices (8). Specify r
30、efer-ence materials made by ion implantation according to ionspecies, isotope, dose, energy, matrix, and reference data usedto calculate peak concentration of the implant in the referencematerial. Report analytical precisions for multiple determina-tions of concentrations.6.4.2 Depth ScalesSpecify t
31、he methods used (if any) torelate elapsed sputter time to a depth sputtered (that is, depthscale calibration). Possible techniques include measurementsof: times to remove reference material films of known thick-ness, ion implant standards with peak concentrations occurringat calculated depths (for e
32、xample, by TRIM of SRIM simula-tion (9), or crater depths via various stylus profilometry orinterferometry techniques. Report any nonuniform sputteringof the specimen, if observed.6.5 Display of SIMS Sputter Depth Profile Figures:6.5.1 Raw Ion Intensity Versus Sputtering Time (or Fluence)ProfilesThe
33、 left hand vertical axis should be ion intensitiesmeasured in arbitrary units (analog detection), or in instanta-neous counts per second (pulse counting, see 6.3.3). Theintensity axis can be either linear or logarithmic dependingupon suitability relative to the dynamic range of the profile.The scale
34、 selected should be clearly indicated. The bottomhorizontal axis should be the sputtering time reported in timeunits or fluence (coulomb/m2or ions/m2). If the primary ionparameters are changed during the profile in a manner thataffects the sputter rate, the time axis must be adjusted accord-ingly.6.
35、5.2 Quantified Depth ProfilesIf elemental concentra-tions or depth scales are quantified as described in 6.4.1 and6.4.2, use the following procedure. The right hand vertical axiscan be reported in units of atomic percent, weight percent, oratoms per cubic metre/centimetre, whichever is most conve-ni
36、ent or appropriate. The top horizontal axis can be indicated inunits of depth (typically nanometres or micrometres). Anexample of the format is shown in Fig. 1 for a11B implantprofile in silicon.E1162 112REFERENCES(1) Hofmann, S., “Quantitative Depth Profiling in Surface Analysis,”Surface and Interf
37、ace Analysis, Vol 2, 1980, p. 148.(2) Zinner, E., “Depth Profiling by Secondary Ion Mass Spectrometry,”Scanning, Vol 3, 1980, p. 57.(3) Wittmaack, K., “Depth Profiling by Means of SIMS: Recent Progressand Current Problems,” Radiation Effects, Vol 63, 1982, p. 205.(4) Williams, P., “Secondary Ion Mas
38、s Spectrometry,” Applied AtomicCollision Physics, Vol 4, 1983, p. 327.(5) Traxlmayr, U., Riedling, K., and Zinner, E., “On the Dead-TimeCorrection of Ion Counting Systems During Gated Raster SIMSMeasurements,” International Journal of Mass Spectrometry and IonProcesses, Vol. 61, 1984, p. 261.(6) Wer
39、ner, H.W., “Quantitative Secondary Ion Mass Spectrometry: AReview,” Surface and Interface Analysis, Vol 2, 1980, p. 56.(7) Wittmaack, K., “Aspects of Quantitative Secondary Ion Mass Spec-trometry,” Nuclear Instruments and Methods, Vol 168, 1980, p. 343.(8) Wilson, R.G., Stevie, F.A., and MAgee, C.W.
40、, Secondary Ion MassSpectrometryA Practical Handbook for Depth Profiling and BulkImpurity Analysis, John Wiley or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).FIG. 1 SIMS Sputter Depth Profile of Boron in SiliconE1162 113
