1、Designation: E 1829 02Standard Guide forHandling Specimens Prior to Surface Analysis1This standard is issued under the fixed designation E 1829; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in
2、 parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide covers specimen handling and preparationprior to surface analysis and applies to the following surfaceanalysis disciplines:1.1.1 Aug
3、er electron spectroscopy (AES),1.1.2 X-ray photoelectron spectroscopy (XPS or ESCA),and1.1.3 Secondary ion mass spectrometry, SIMS.1.1.4 Although primarily written for AES, XPS, and SIMS,these methods may also apply to many surface-sensitiveanalysis methods, such as ion scattering spectrometry, low-
4、energy electron diffraction, and electron energy loss spectros-copy, where specimen handling can influence surface-sensitivemeasurements.1.2 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 e
5、stablish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:E 673 Terminology Relating to Surface Analysis2E 1078 Guide for Specimen Preparation and Mounting inSurface Analysis23. Terminology3.1 D
6、efinitionsFor definitions of surface analysis termsused in this guide, see Terminology E 673.4. Significance and Use4.1 Proper handling and preparation of specimens is par-ticularly critical for analysis. Improper handling of specimenscan result in alteration of the surface composition and unreli-ab
7、le data. Specimens should be handled carefully so as to avoidthe introduction of spurious contaminants. The goal must be topreserve the state of the surface so that analysis remainsrepresentative of the original subject.4.2 Auger electron spectroscopy (AES), X-ray photoelec-tron spectroscopy (XPS),
8、and secondary ion mass spectroscopy(SIMS) are sensitive to surface layers that are typically a fewnanometres thick. Such thin layers can be subject to severeperturbations from improper specimen handling (1).34.3 This guide describes methods to minimize the effects ofspecimen handling on the results
9、obtained using surface-sensitive analytical techniques. It is intended for the specimenowner or the purchaser of surface analytical services and thesurface analyst. Because of the wide range of types ofspecimens and desired information, only broad guidelines andgeneral examples are presented here. T
10、he 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 withregard to specimen history, the specific problem to be solved orinformation needed, and the particular
11、 specimen preparation orhandling procedures required. The surface analyst also isreferred to Guide E 1078 that discusses additional proceduresfor preparing, mounting, and analysis of specimens.5. General Requirements5.1 The degree of cleanliness required by surface-sensitiveanalytical techniques oft
12、en is much greater than for other formsof analysis.5.2 Specimens must never be in contact with the bare hand.Handling of the surface to be analyzed should be eliminated orminimized whenever possible.5.3 Specimens should be transported to the analyst in acontainer that does not come into direct conta
13、ct with thesurface of interest.5.4 In most cases, the analysis will be performed on the “asreceived” specimen. Surface contamination or atmosphericadsorbates are not usually removed because of the importanceof analyzing an unaltered surface and as these are often theregions of interest. Care must th
14、en be taken in the handling thespecimen to ensure that no outside agents come in contact withthe surface to be investigated. These agents include: solvents orcleaning solutions, gases (including compressed air) or vapors,metals, tissue or other wrapping materials, tape, cloth, tools,packing material
15、s or the walls of containers. If the specimen1This guide is under the jurisdiction of ASTM Committee E42 on SurfaceAnalysis and is the direct responsibility of Subcommittee E42.03 on Auger ElectronSpectroscopy and X-ray Photoelectron Spectroscopy.Current edition approved April 10, 2002. Published Ap
16、ril 2002. Originallypublished as E 1829 96. Last previous edition E 1829 97.2Annual Book of ASTM Standards, Vol 03.06.3The boldface numbers in parentheses refer to the list of references at the end ofthis standard.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken,
17、PA 19428-2959, United States.supplier is uncertain of the requirements for a specific speci-men, they should consult the analyst.5.5 In some cases (for example, for a large specimen), itmay be necessary to take a representative sample from thespecimen. Selection of a smaller sample from a larger spe
18、ci-men should be done while considering the information beingsought because inhomgeneities are often present. It is recom-mended that this choice be made in consultation with anexperienced analyst.5.6 Numerous methods exist for the mounting of a specimenin preparation for analysis. Refer to Guide E
19、1078.5.7 Hazardous MaterialsSpecial caution shall be exer-cised with specimens containing potential toxins or otherhazardous materials. Whenever possible chemical hazard datasheets should be supplied with the specimen.5.8 The severity of the requirement for specimen handlingvaries dramatically with
20、the condition of the surface and thelocation of the information being sought. The list in AppendixX1 describes types of specimens by their increasing sensitivityto handling.6. Specimen Influences6.1 The analyst should be advised of the specimen history,special storage or transport requirements, expo
21、sure to possiblecontaminants, and the information being sought.6.2 HistoryThe history of a specimen can influence thehandling of its surface. For example, a specimen that has beenpreviously exposed to a contaminating environment mayreduce the need for exceptional care if the surface becomes lessreac
22、tive. Alternatively, the need for care may increase if thesurface becomes toxic.6.3 Specimens Previously Examined by Other AnalyticalTechniquesIt is best if surface analysis measurements aremade before the specimen is analyzed by other analyticaltechniques because such specimens may become damaged o
23、rmay be exposed to surface contamination. For example,insulating specimens analyzed by electron microscopy mayhave been coated to reduce charging. This coating renders thespecimens unsuitable for subsequent surface analysis. Expo-sure to an electron beam (for example, in a SEM) also caninduce damage
24、 or deposit additional contamination. If it is notpossible to perform the surface analysis work first, then theanalysis should be done on a different, but nominally identical,specimen or area of the specimen.6.4 Information SoughtSurface chemical analysis can beperformed on a wide range of specimens
25、 and can be used toobtain very different types of information about surfaces orinterfaces. The degree of care that must to be taken dependsupon the type of analysis that is required and the nature of theproblem. The information being sought usually falls into fourgeneral categories: (A) information
26、on the outermost surface;(B) information as a function of depth (depth profile) or at aburied interface; and (C) information that will require subse-quent specimen preparation by the analyst.6.4.1 Type A specimens include those to be investigated forsurface contamination, surface stains, and adhesio
27、n failures.This category requires the most care in preparation andpackaging. Ideally, nothing should be allowed to contact thesurface of interest. In practice, it may be necessary to wrap thesamples to avoid damage in transit. (See Appendix X3.)6.4.2 Type B specimens include those that require thein
28、vestigation of thick and thin films, single layers, multilayers,metal contact layers on semiconductors, coatings, dopantprofiles, and the chemical and physical properties at aninterface between two dissimilar materials. For this categorythe packaging requirements are not as stringent although caresh
29、ould still be taken to not contaminate the specimen. In thisclass, the information sought comes from a layer below theoutermost surface and superficial surface contamination is notan issue. With semiconductor samples, care should be taken toavoid particulate contamination of the surface as this cand
30、egrade the quality of the depth profiles.6.4.3 Type C specimens include those that require prepara-tion by the analyst and includes specimens for in-situ fracture,metallurgical lapping or polishing, and specimens that are partof a larger assembly. Generally, these specimens must beshaped (for exampl
31、e, for fracture), chemically or mechanicallyaltered (as happens with lapping) or disassembled. Few specialprecautions are needed for samples that are to be fractured, orundergo further sample preparation by the analyst. For speci-men in a larger assembly or subassembly, it may be preferableto leave
32、the specimen in place and let the analyst remove it foranalysis. Nonetheless, care should still be taken to not con-taminate the specimen.6.5 Clearly identify all specimens with a unique name oridentifier. If it is possible to permanently attach this identifier tothe specimen (without disturbing the
33、 area of interest), do so.Clearly indicate the area of analysis by marking up a drawingor a photograph. If necessary, a scribe or permanent ink markercan be used on an area adjacent to the areas of interest. If thereis any doubt as to which side of the specimen is to be analyzed,clearly mark the bac
34、k of the specimen.6.6 PrecautionsDo not touch the surface of interest, eitherby hand or with a tool. Do not “protect” the surface of interestby covering it with tape, contaminated foil or porous wrappingmaterial. Do not use a diamond scribe to mark semiconductors.Fragile specimens should not be moun
35、ted onto double-sidedtape.7. Sources of Specimen Contamination7.1 An unprotected hand must never handle specimens,even when the skin will not touch the surface of interest.Fingerprints and hand creams contain mobile species that maymigrate and contaminate the surface of interest.7.2 Handling of spec
36、imens only should be done with cleantools to ensure that the specimen surface is not altered prior toanalysis. Tools should be made of materials that do not transferto the specimen or introduce spurious contaminants ontosurfaces (for example, Ni tools contaminate Si). Tools shouldbe cleaned regularl
37、y in high-purity solvents and dried prior touse. Nonmagnetic tools should be used if the specimen issusceptible to magnetic fields. Tools should never unnecessar-ily touch the specimen surface.7.3 Although gloves and wiping materials are sometimesused to handle specimens, it is likely that their use
38、 will resultin some contamination. Care should be taken to avoid con-tamination by talc, silicone compounds, and other materialsthat are often found on gloves. “Powder-free” gloves have noE 18292talc and may be better suited. The surface to be analyzedshould never be touched by the glove or other to
39、ol unlessnecessary.7.4 Blowing on the specimen using a compressed gas source(for example, to remove particulates) is likely to cause con-tamination even when using a noble gas (such as argon orhelium) because of the likelihood that the nozzle or thedelivery line may contain oils, organics or particu
40、lates. Blow-ing with the mouth is not recommended.7.5 To minimize the potential for contamination of the areato be analyzed during handling, the preparer should select oneof the methods in the list in Appendix X2.8. Specimen Storage and Transfer8.1 Storage:8.1.1 TimeThe longer a specimen is in stora
41、ge, the morecare must be taken to ensure that the surface to be analyzed hasnot been contaminated. Even in clean laboratory environments,surfaces can become contaminated quickly to the depth ana-lyzed by AES, XPS, SIMS, and other surface sensitive analyti-cal techniques.8.1.2 Containers:8.1.2.1 Cont
42、ainers suitable for storage should not transfercontaminants to the specimen by means of particles, liquids,gases, or surface diffusion. Keep in mind that volatile species(for example, plasticizers) may be emitted from such contain-ers, further contaminating the surface. Preferably, the surfaceto be
43、analyzed should not contact the container or any otherobject. Glass jars with an inside diameter slightly larger thanthe width of a specimen can hold a specimen without contactwith the surface. When contact with the surface is unavoidable,wrapping in clean, preanalyzed aluminum foil may be satis-fac
44、tory. For semiconductor samples, standard wafer carriers aregenerally adequate.8.1.2.2 Containers, such as glove boxes, vacuum chambers,and desiccators may be excellent choices for storage ofspecimens. A vacuum desiccator may be preferable to astandard unit and should be maintained free of grease an
45、dmechanical pump oil. Cross contamination between specimensalso may occur if multiple specimens are stored together.8.1.3 Temperature and HumidityPossible temperature andhumidity effects should be considered when storing or shippingspecimens. Most detrimental effects result from elevated tem-peratur
46、es. Additionally, low specimen temperatures can lead tomoisture condensation on the surface.8.2 Transfer:8.2.1 ChambersChambers that allow transfer of speci-mens from a controlled environment to an analytical chamberhave been reported (2,3,4). Controlled environments could beother vacuum chambers, g
47、love boxes (dry boxes), glove bags,reaction chambers, and so forth, which can be attached directlyto an analytical chamber with the transfer made through apermanent valve. Glove bags can be attached temporarily to ananalytical chamber with transfer of a specimen done byremoval and then replacement o
48、f a flange on the analyticalchamber.8.2.2 CoatingsCoatings can sometimes be applied tospecimens allowing transfer in atmosphere. The coating then isremoved by heating or vacuum pumping in either the analyticalchamber or its introduction chamber. This concept has beenapplied successfully to the trans
49、fer of GaAs (5). Surfaces to beanalyzed by SIMS or AES can be covered with a uniform layer,such as polysilicon for silicon-based technology (6). In thiscase, the coating is removed during analysis.8.2.3 Material TransferMaterial transfer can be of valuewhen the specimen is too large to be inserted into an analyticalchamber or is needed for other purposes. The film or particlesto be analyzed must transfer from the specimen to thereplicating compound or tape. The replicating compoundshould be conductive for analysis by AES or SIMS (7). Caremust be taken to ensure that the mate
