1、Designation: F1710 08 (Reapproved 2016)Standard Test Method forTrace Metallic Impurities in Electronic Grade Titanium byHigh Mass-Resolution Glow Discharge Mass Spectrometer1This standard is issued under the fixed designation F1710; the number immediately following the designation indicates the year
2、 oforiginal adoption or, in the case of revision, 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 test method covers the determination of concentra-t
3、ions of trace metallic impurities in high purity titanium.1.2 This test method pertains to analysis by magnetic-sectorglow discharge mass spectrometer (GDMS).1.3 The titanium matrix must be 99.9 weight % (3N-grade)pure, or purer, with respect to metallic impurities. There mustbe no major alloy const
4、ituent, for example, aluminum or iron,greater than 1000 weight ppm in concentration.1.4 This test method does not include all the informationneeded to complete GDMS analyses. Sophisticated computer-controlled laboratory equipment skillfully used by an experi-enced operator is required to achieve the
5、 required sensitivity.This test method does cover the particular factors (for example,specimen preparation, setting of relative sensitivity factors,determination of sensitivity limits, etc.) known by the respon-sible technical committee to effect the reliability of high puritytitanium analyses.1.5 T
6、his 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 the applica-bility of regulatory limitations prior to use.2. Referenced Docume
7、nts2.1 ASTM Standards:2E135 Terminology Relating to Analytical Chemistry forMetals, Ores, and Related MaterialsE173 Practice for Conducting Interlaboratory Studies ofMethods for Chemical Analysis of Metals (Withdrawn1998)3E180 Practice for Determining the Precision of ASTMMethods for Analysis and Te
8、sting of Industrial and Spe-cialty Chemicals (Withdrawn 2009)3E691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodE1257 Guide for Evaluating Grinding Materials Used forSurface Preparation in Spectrochemical Analysis3. Terminology3.1 Terminology in this tes
9、t method is consistent withTerminology E135. Required terminology specific to this testmethod, not covered in Terminology E135, is indicated in 3.2.3.2 Definitions:3.2.1 campaigna series of analyses of similar specimensperformed in the same manner in one working session, usingone GDMS setup.3.2.1.1
10、DiscussionAs a practical matter, cleaning of theion source specimen cell is often the boundary event separatingone analysis campaign from the next.3.2.2 reference samplematerial accepted as suitable foruse as a calibration/sensitivity reference standard by all partiesconcerned with the analyses.3.2.
11、3 specimena suitably sized piece cut from a referenceor test sample, prepared for installation in the GDMS ionsource, and analyzed.3.2.4 test samplematerial titanium to be analyzed for tracemetallic impurities by this GDMS method.3.2.4.1 DiscussionGenerally the test sample is extractedfrom a larger
12、batch (lot, casting) of product and is intended tobe representative of the batch.4. Summary of the Test Method4.1 A specimen is mounted as the cathode in a plasmadischarge cell. Atoms subsequently sputtered from the speci-men surface are ionized, and then focused as an ion beam1This test method is u
13、nder the jurisdiction of ASTM Committee F01 onElectronics and is the direct responsibility of Subcommittee F01.17 on SputterMetallization.Current edition approved May 1, 2016. Published May 2016. Originallyapproved in 1996. Last previous edition approved in 2008 as F1710 08. DOI:10.1520/F1710-08R16.
14、2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is ref
15、erenced onwww.astm.org.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1through a double-focusing magnetic-sector mass separationapparatus. The mass spectrum, that is, the ion current, iscollected as magnetic field or acceleration volt
16、age, or both, isscanned.4.2 The ion current of an isotope at mass Miis the totalmeasured current, less contributions from all other interferingsources. Portions of the measured current may originate fromthe ion detector alone (detector noise). Portions may be due toincompletely mass resolved ions of
17、 an isotope or molecule withmass close to, but not identical with, Mi. In all such instancesthe interfering contributions must be estimated and subtractedfrom the measured signal.4.2.1 If the source of interfering contributions to the mea-sured ion current at Micannot be determined unambiguously,the
18、 measured current less the interfering contributions fromidentified sources constitutes an upper bound of the detectionlimit for the current due to the isotope.4.3 The composition of the test specimen is calculated fromthe mass spectrum by applying a relative sensitivity factor(RSF(X/M) for each con
19、taminant element, X, compared to thematrix element, M . RSFs are determined in a separate analysisof a reference material performed under the same analyticalconditions, source configuration, and operating protocol as forthe test specimen.4.4 The relative concentrations of elements X and Y arecalcula
20、ted from the relative isotopic ion currents I(Xi) and I(Yj)in the mass spectrum, adjusted for the appropriate isotopicabundance factors (A(Xi), A(Yj) and RSFs. I(Xi) and I(Yj) referto the measured ion current from isotopes Xiand Yj,respectively, of atomic species X and Y as follows:X#/Y# 5 RSFX/M!/R
21、SFY/M! 3 AYj!/AXi! 3 IXi!/IYj!, (1)where (X)/(Y) is the concentration ratio of atomic species Xto species Y. If species Y is taken to be the titanium matrix(RSF(M/M) = 1.0), (X) is (with only very small error for puremetal matrices) the absolute impurity concentration of X.5. Significance and Use5.1
22、 This test method is intended for application in thesemiconductor industry for evaluating the purity of materials(for example, sputtering targets, evaporation sources) used inthin film metallization processes. This test method may beuseful in additional applications, not envisioned by the respon-sib
23、le technical committee, as agreed upon between the partiesconcerned.5.2 This test method is intended for use by GDMS analystsin various laboratories for unifying the protocol and parametersfor determining trace impurities in pure titanium. The objectiveis to improve laboratory to laboratory agreemen
24、t of analysisdata. This test method is also directed to the users of GDMSanalyses as an aid to understanding the determination method,and the significance and reliability of reported GDMS data.5.3 For most metallic species the detection limit for routineanalysis is on the order of 0.01 weight ppm. W
25、ith specialprecautions detection limits to sub-ppb levels are possible.5.4 This test method may be used as a referee method forproducers and users of electronic-grade titanium materials.6. Apparatus6.1 Glow Discharge Mass Spectrometer, with mass resolu-tion greater than 3500, and associated equipmen
26、t and supplies.The GDMS must be fitted with an ion source specimen cell thatis cooled by liquid nitrogen, Peltier cooled, or cooled by anequivalent method.6.2 Machining Apparatus, capable of preparing specimensand reference samples in the required geometry and withsmooth surfaces.7. Reagents and Mat
27、erials7.1 Reagent and High Purity Grade Reagents, as required(MeOH, HNO3,HF,H2O2).7.2 Demineralized Water.7.3 Tantalum Reference Sample.7.4 Titanium Reference Sample.7.4.1 To the extent available, titanium reference materialsshall be used to produce the GDMS relative sensitivity factorsfor the vario
28、us elements being determined (Table 1).7.4.2 As necessary, non-titanium reference materials may beused to produce the GDMS relative sensitivity factors for thevarious elements being determined.7.4.3 Reference materials should be homogeneous and freeof cracks or porosity.7.4.4 At least two reference
29、materials are required to estab-lish the relative sensitivity factors, including one nominally99.999 % pure (5N-grade) or better titanium metal to establishthe background contribution in analyses.7.4.5 The concentration of each analyte for relative sensi-tivity factor determination should be a facto
30、r of 100 greaterthan the detection limit determined using a nominally99.999 % pure (5N-grade) or better titanium specimen, but lessthan 100 ppmw.7.4.6 To meet expected analysis precision, it is necessarythat specimens of reference and test material present the samesize and configuration (shape and e
31、xposed length) in the glowdischarge ion source, with a tolerance of 0.2 mm in diameterand 0.5 mm in the distance of specimen to cell ion exit slit.8. Preparation of Reference Standards and TestSpecimens8.1 The surface of the parent material must not be includedin the specimen.8.2 The machined surfac
32、e of the specimen must be cleanedby chemical etching immediately prior to mounting the speci-men and inserting it into the glow discharge ion source.8.2.1 In order to obtain a representative bulk composition ina reasonable analysis time, surface cleaning must remove allcontaminants without altering
33、the composition of the specimensurface.8.2.2 To minimize the possibility of contamination, cleaneach specimen separately immediately prior to mounting in theglow discharge ion source.8.2.3 Prepare and use etching solutions in a clean containerinsoluble in the contained solution.8.2.4 Useful etching
34、solutions are HNO3:HF:3:1 orHNO3:HF:H2O2: :1:1:1 or H2O:HNO3:HF:H2O2:20:5:5:4F1710 08 (2016)2(double etched), etching until smooth, clean metal is exposedover the entire surface.8.2.5 Immediately after cleaning, wash the specimen withhigh purity rinses and thoroughly dry the specimen in thelaborator
35、y environment.NOTE 1Examples of acceptable high purity rinses are very large scaleintegration (VLSI) grade methanol and distilled water.8.3 Immediately mount and insert the specimen into theglow discharge ion source, minimizing exposure of thecleaned, rinsed, specimen surface to the laboratory envir
36、on-ment.8.3.1 As necessary, use a noncontacting gage when mount-ing specimens in the analysis cell specimen holder to ensurethe proper sample configuration in the glow discharge cell (see7.4.6).8.4 Sputter etch the specimen surface in the glow dischargeplasma for a period of time before data acquisi
37、tion (12.3)toensure the cleanliness of the surface. Pre-analysis sputteringconditions can be limited by the need to maintain sampleintegrity. If sputter cleaning and analysis are carried out underdifferent plasma conditions, accuracy should be established forthe analytical protocol adopted and eleme
38、nts measured.9. Preparation of the GDMS Apparatus9.1 The ultimate background pressure in the ion sourcechamber should be less than 1 106torr before operation.Thebackground pressure in the mass analyzer should be less than5107torr during operation.9.2 The glow discharge ion source must be cooled to n
39、earliquid nitrogen temperature.9.3 The GDMS instrument must be accurately mass cali-brated prior to measurements.9.4 The GDMS instrument must be adjusted to the appro-priate mass peak shape and mass resolving power for therequired analysis.9.5 If the instrument uses different ion collectors to measu
40、reion currents during the same analysis, the measurement effi-ciency of each detector relative to the others should bedetermined at least weekly.9.5.1 If both Faraday cup collector for ion current measure-ment and ion counting detectors are used during the sameanalysis, the ion counting efficiency (
41、ICE) must be determinedprior to each campaign of specimen analyses using the follow-ing or equivalent procedures:9.5.1.1 Using a specimen of tantalum, measure the ioncurrent from the major isotope (181Ta) using the ion currentFaraday cup detector, and measure the ion current from theminor isotope (1
42、80Ta) using the ion counting detector, with careto avoid ion counting losses due to ion-counting system deadtimes. The counting loss should be 1 % or less.9.5.1.2 The ion counting efficiency is calculated by multi-plying the ratio of the180Ta ion current to the181Ta ion currentby the181Ta/180Ta isot
43、opic ratio. The result of this calculationis the ion counting detector efficiency (ICE).TABLE 1 Suite of Impurity Elements to be Analyzed, withAppropriate Isotope SelectionNOTE 1Establish RSFs for the following suite of elements, using theindicated isotopes for establishing RSF values and for perfor
44、minganalyses of test specimens.NOTE 2This selection of isotopes minimizes significant interferences(see Annex A1.). Additional species may be determined and reported, asagreed upon by all parties concerned with the analyses. Other isotopes canbe selected to assist mass spectrum peak identification o
45、r for otherpurposes.LithiumBerylliumBoronCarbonNitrogenOxygenFluorineSodiumMagnesiumAluminumSiliconPhophorusSulfurChlorinePotassiumCalciumScandiumTitaniumVanadiumChromiumManganeseIronCobaltNickelCopperZincGalliumGermaniumArsenicSeleniumBromineRubidiumYttriumZirconiumNiobiumMolybdenumRutheniumRhodium
46、SilverPalladiumCadmiumIndiumTinAntimonyIodineTelluriumCesiumBariumLanthanumCeriumNeodymiumHafniumTantalumTungstenRheniumOsmiumIridiumPlatinumGoldMercuryThalliumLeadBismuthThoriumUranium7Li9Be11B12C14N16O19F23Na26Mg27Al28Si31P32S35Cl39K42Ca45Sc48Ti51V52Cr55Mn56Fe59Co60Ni63Cu66Zn or68Zn69Ga or71Ga70Ge
47、 or73Ge75As77Se79Br85Rb89Y91Zr93Nb100Mo101Ru103Rh107Ag106Pd or108Pd114Cd115In117Sn or119Sn121Sb127I125Te or130Te133Cs138Ba139La140Ce146Nd176Hf or178Hf181Ta184W187Re190Os or192Os191Ir194Pt or196Pt197Au201Hg or202Hg205Tl208Pb209Bi232Th238UF1710 08 (2016)39.5.1.3 Apply the ICE as a correction to all io
48、n currentmeasurements from the ion counting detector obtained inanalyses by dividing the ion current by the ICE factor.10. Instrument Quality Control10.1 A well-characterized specimen must be run on aregular basis to demonstrate the capability of the GDMSsystem as a whole for the required analyses.1
49、0.2 A recommended procedure is the measurement of therelative ion currents of selected analytes and the matrixelement in titanium or tantalum reference samples.10.3 Plot validation analysis data from at least five elementswith historic values in statistical process control (SPC) chartformat to demonstrate that the analysis process is in statisticalcontrol. The equipment is suitable for use if the analysis datagroup is within the 3-sigma control limits and shows nononrandom trends.10.4 Upper and lower control limits for SPC must be withinat least 20 % of
