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  • Designation: D 5077 90 (Reapproved 1997)

    Standard Terminology Relating toElectrostatic Discharge (ESD) Packaging Materials1This standard is issued under the fixed designation D 5077; 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 parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.

    1. Scope1.1 The terms and definitions in this standard are related to

    Electrostatic Discharge (ESD) Packaging Materials and ESDProtective Materials.2. Referenced Documents2.1 ASTM Standards:D 996 Terminology Relating to Packaging and DistributionEnvironments2

    2.2 EIA Standard:EIA-541 Packaging Material Standards for ESD, SensitiveItems3

    3. Terminologyantistatic agenta chemical compound which, when impreg-nated or formulated into or topically applied to a primarymaterial or substrate, gives the primary material antistaticproperties. See antistatic property.

    antistatic propertythe prevention of triboelectric chargegeneration by effectively minimizing the production of astatic charge when materials are separated from anothersurface.DISCUSSIONThe forword of EIA-541 states, 8Antistatic no longer

    refers to a resistivity range ... 8Antistatic refers to a materials abilityto resist triboelectric charge generation. A materials antistatic propen-sity depends upon the nature of the material itself and the material withwhich it is in contact along with the means of surface separation. Theantistatic property is not a dependent function of material resistivity.Material resistivity is an intrinsic property used to define its degree ofconductivity without regard to other materials.

    conductora substance or body that allows a flow of electriccurrent to pass continuously along it or through it when asufficient voltage is applied across any two points.

    dielectric breakdowna threshold effect in a dielectric me-dium where, at some electric field strength across themedium, bound electrons become unbound and travelthrough the medium as a current. In solid media, the regionof the current path is permanently damaged. The unit ofmeasurement is usually volts per unit of thickness.

    electrically continuous surfacea surface that is electricallyconductive in that current can be passed at an applied voltagebetween any two points of its physical surface.

    electrical overstress (EOS)overstress which may be due toESD or the operation of items beyond their electricalspecifications.

    electromagnetic shielda screen or other housing placedaround a device or circuit to reduce the effects on them fromboth electric and magnetic fields.

    electrostatic dischargethe transfer of electrostatic chargebetween bodies at different electrostatic potentials.

    electrostatic discharge (ESD) protectivea property of ma-terials capable of one or more of the following:preventing the generation of static electricity.dissipating electrostatic changes over its surface or volume.providing shielding from ESD or electrostatic fields.

    electrostatic discharge sensitive (ESDS)a property of itemsin which they are inherently sensitive (ESDS) susceptible toeither catastrophic failure or latent damage when exposed tosources of ESD. Items are often categorized as to their levelsof sensitivity but in all cases require some means of ESDprotective packaging and handling.

    electrostatic shielda barrier or enclosure that prevents thepenetration of an electrostatic field.DISCUSSIONAn electrostatic shield may not offer much protection

    against the effects of an electromagnetic field. Electromagnetic shields,however, are good electrostatic shields.

    grounda metallic connection with the earth to establish zeropotential.DISCUSSIONThe ground is the voltage reference point in a circuit.

    There may or may not be an actual connection to earth, but it isunderstood that a point in the circuit said to be at ground potential couldbe connected to earth without disturbing the operation of the circuit inany way. Grounds that can be used for static control work stationsinclude metal water pipes, any power ground, or any large metalstructural member of a building, vessel hull, etc. (See grounding.)

    groundingconnecting to ground or to a conductor that isgrounded.

    insulator (electric)a device having high electrical resistanceand used for supporting or separating conductors to preventundesired flow of current from them to other objects. (Alsoknown as electrical insulator.)

    ionizationthe process by which neutral atoms or molecules,such as air, acquire a positive or negative charge.

    packagingSee Terminology D 996.

    1 This terminology is under the jurisdiction of ASTM Committee D-10 onPackaging and is the direct responsibility of Subcommittee D10.13 on InteriorPackaging.

    Current edition approved June 29, 1990. Published August 1990.2 Annual Book of ASTM Standards, Vol 15.09.3 Available from the Electronic Industries Association, 2001 Eye St., N.W.,

    Washington, DC 20006.

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    AMERICAN SOCIETY FOR TESTING AND MATERIALS100 Barr Harbor Dr., West Conshohocken, PA 19428

    Reprinted from the Annual Book of ASTM Standards. Copyright ASTM

    NOTICE:Thisstandardhaseitherbeensupercededandreplacedbyanewversionordiscontinued.ContactASTMInternational(www.astm.org)forthelatestinformation.

  • DISCUSSIONThe term packaging as used in this context should notbe confused with the term as it is used in the electronics industry whereit describes the assembly, black box enclosure, or physical encasing ofmicroelectronic devices.

    surface resistivity, rsthe surface resistivity of a material isthe ratio of the potential gradient parallel to the current alongits surface to the current per unit width of the surface.DISCUSSIONSurface resistivity of a material is numerically equal to

    the surface resistance between two electrodes forming opposite sides ofa square. The size of the square is immaterial.

    volume resistivity, rvthe volume resistivity of a material isthe ratio of the potential gradient parallel to the current in thematerial to the current density.

    DISCUSSIONIn the metric system, volume resistivity of an electricalinsulating material in ohm-cm is numerically equal to the volumeresistance in ohms between opposite faces of a 1-cm cube of thematerial. (Volume resistivity inV m has a value of 1100 of the value inV cm.)

    This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM Headquarters. Your comments will receive careful consideration at a meeting of the responsibletechnical committee, which you may attend. If you feel that your comments have not received a fair hearing you should make yourviews known to the ASTM Committee on Standards, 100 Barr Harbor Drive, West Conshohocken, PA 19428.

    D 5077

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    NOTICE:Thisstandardhaseitherbeensupercededandreplacedbyanewversionordiscontinued.ContactASTMInternational(www.astm.org)forthelatestinformation.