ASTM_F_71_-_68_1999.pdf

Designation:F 71 68(Reapproved 1999)An American National StandardStandard Practice forUsing the Morphological Key for the Rapid Identification ofFibers for Contamination Control in Electron Devices andMicroelectronics1This standard is issued under the fixed designation F 71;the number immediately following the designation indicates the year of originaladoption or,in the case of revision,the year of last revision.Anumber in parentheses indicates the year of last reapproval.Asuperscriptepsilon(e)indicates an editorial change since the last revision or reapproval.1.Scope1.1 This practice covers the rapid identification of nonme-tallic,fibrous contaminants by the microscopical examinationof their morphology.The procedure is intended either toprovide tentative identification or to serve as a supporting testin confirming the identity of suspected fibrous contaminants.21.2 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 establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:D 276 Method for Identification of Fibers in Textiles2F 25 Test Method for Sizing and Counting Airborne Par-ticulate Contamination in Clean Rooms and Other Dust-Controlled Areas Designed for Electronic and SimilarApplications33.Terminology3.1 Definitions:3.1.1 fibera particle longer than 100 m with a length-to-diameter ratio of greater than 10:1.For this practice,thedefinition includes organic and inorganic fibers,both naturaland synthetic,but excludes metal fibers.See Fig.1(r).3.1.2 medullaa distinct center portion of a fiber.See Fig.1(c).3.1.3 lumena canal or central opening in the fiber.SeeFig.1(b).3.1.4 septswalls separating cavities in the fiber.See Fig.1(d).3.1.5 scalessurface plate-like formations.See Fig.1(a)and(h).4.Summary of Practice4.1 This practice comprises the collection and mounting offibers and their examination by transmitted light.The fibermorphology is observed for its dimensions and external andinternal structure and is compared to a morphological keyanalysis chart for classification.5.Apparatus5.1 Microscope,approximately 100 and 4003 magnifica-tion,with mechanical stage,substage illumination,and con-denser to provide transmitted light.The optimum equipment isa binocular microscope with mechanical stage,substage illu-mination,and substage condenser having 103 eyepieces andappropriate objectives to provide approximately 00 and 4003magnification.5.2 Microscope Lamp,required only when substage lightsource not provided with microscope.5.3 Ocular Micrometer Scale.45.4 Stage Micrometer,standard 0.01-to 01-mm scale.55.5 Glass Microscope Slides.5.6 Immersion Oil,refractive index 1.51.5.7 Microscope Slide Cover Glasses.6.Sampling6.1 Sample airborne fibers in accordance with Test MethodF 25.6.2 Sample fibers on surfaces,by removing the fiber fromthe surface and placing it on a glass microscope slide,usingappropriate forceps.7.Calibration7.1 Calibrate the ocular micrometer in accordance with theprocedure described in Test Method F 25.8.Specimen Preparation8.1 If the fiber has been collected directly on a microscopeslide,cover it with a cover glass.8.2 If the fiber has been collected on the surface of amembrane filter,place the filter on a glass microscope slide andrender the filter transparent by placing five drops of immersion1This practice is under the jurisdiction of ASTM Committee E-21 on SpaceSimulation and Applications of Space Technology and is the direct responsibility ofSubcommittee E21.05 on Contamination.Current edition approved Aug.15,1968.Published October 1968.Originallypublished as F 71 66 T.Last previous edition F 7166 T.2For more detailed procedures of fiber identification,see Test Methods D 276,which appears in the Annual Book of ASTM Standards,Vol 07.01,also M.R.Harris,Handbook of Textile Fibers,and H.R.Mauersberger,Matthews Textile Fibers,6thedition.3Annual Book of ASTM Standards,Vol 15.03.4B&L 31-61-01 or equivalent has been found satisfactory for this purpose.5B&L 31-16-90 or equivalent has been found satisfactory for this purpose.1Copyright ASTM,100 Barr Harbor Drive,West Conshohocken,PA 19428-2959,United States.oil on top of the slide and then placing the filter on top of theimmersion oil.Cover the saturated filter with a microscopecover glass.9.Procedure9.1 Using a magnification of 1003 and the calibrated ocularmicrometer with transmitted light,measure the fiber diameter.For fibers with nonuniform diameters or for multifilamentfibers,make the measurements at several different points alonga single fiber or on several different fibers and calculate anaverage diameter.9.2 Examine the fiber at 1003 magnification for the follow-ing features:FIG.1 Examples of Fibers(1003 Magnification)F 7129.2.1 Surface scales,9.2.2 Lumen,9.2.3 Cross markings or longitudinal striations,9.2.4 Fiber wall appearance,9.2.5