ASTM_F_72_-_95_2001.pdf

Designation:F 72 95(Reapproved 2001)Standard Specification forGold Wire for Semiconductor Lead Bonding1This standard is issued under the fixed designation F 72;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 specification covers round drawn/extruded goldwire for internal semiconductor device electrical connections.Four classifications of wire are distinguished,(1)copper-modified wire,(2)beryllium-modified wire,(3)high-strengthwire,and(4)special purpose wire.NOTE1Trace metallic elements have a significant effect upon themechanical properties and thermal stability of high-purity gold wire.It iscustomary in manufacturing to add controlled amounts of selectedimpurities to gold to modify or stabilize bonding wire properties or both.This practice is known variously as“modifying,”“stabilizing,”or“doping.”The first two wire classifications denoted in this specificationrefer to wire made with either of two particular modifiers,copper orberyllium,in general use.In the third and fourth wire classifications,“high-strength”and“special purpose”wire,the identity of modifyingadditives is not restricted.1.2 The values stated in SI units shall be regarded as thestandard.1.2.1 A mixed system of metric and inch-pound units is inwidespread use for specifying semiconductor lead-bondingwire.SI-equivalent values of other commonly used units aredenoted by parentheses in text and tables.1.3 The following hazard caveat pertains only to the testmethod portion,Section 9,of this specification.This standarddoes not purport to address all of the safety concerns,if any,associated with its use.It is the responsibility of the user of thisstandard to establish appropriate safety and health practicesand determine the applicability of regulatory limitations priorto use.2.Referenced Documents2.1 ASTM Standards:F 16 Test Methods for Measuring Diameter or Thickness ofWire and Ribbon for Electronic Devices and Lamps2F 205 Test Method for Measuring Diameter of Fine Wireby Weighing2F 219 Test Methods of Testing Fine Round and Flat Wirefor Electron Devices and Lamps2F584 Practice for Visual Inspection of SemiconductorLead-Bonding Wire23.Ordering Information3.1 Orders for material under this specification shall includethe following information:3.1.1 Classification:copper-modified,beryllium-modified,high strength,or special purpose,3.1.2 Quantity,3.1.3 Purity(Section 4),3.1.4 Type,hard,stress relieved,or annealed(Section 5),3.1.5 Breaking load and percentage elongation range(Sec-tion 5),3.1.6 Wire diameter(Section 6),3.1.7 Spool type,length of wire per spool,and type of wind(Section 11),3.1.8 Despooling,left-handed unwind or right-handed un-wind(Section 11),and,3.1.9 Packaging and marking(Section 12).4.Chemical Composition4.1 Copper-modified material shall conform to the chemicalrequirements specified in Table 1.4.2 Beryllium-modified material shall conform to thechemical requirements specified in Table 2.4.3 High-strength material shall conform to the chemicalrequirements specified in Table 3.4.4 Special purpose material shall be in accordance withTable 4.NOTE2Copper-modified wire is used on thermocompression wirebonding machines.Beryllium-modified material is often preferred onhigh-speed automated thermocompression or thermosonic bonding equip-ment.High-strength wire was developed for use on some very high speedautomated thermosonic bonders.5.Mechanical Properties5.1 Material specified by this standard may be either of twotypes:5.1.1 HardWire,as drawn/as extruded.5.1.2 AnnealedWire,annealed after drawing/extruding.5.2 Breaking Load and ElongationThe tension test shallbe the standard test for determining the mechanical properties,and acceptance or rejection shall depend on the breaking loadand percent elongation at failure of a 254-mm(10.0-in.)lengthof wire.5.2.1 Hard wire shall conform to the requirements of Table5 for copper-modified gold wire and to the requirements ofTable 6 for beryllium-modified gold wire.1This specification is under the jurisdiction of ASTM Committee F01 onElectronics and is the direct responsibility of Subcommittee F01.07 on WireBonding.Current edition approved April 15,1995.Published June 1995.Originallypublished as F 72 66 T.Last previous edition F 72 94.2Annual Book of ASTM Standards,Vol 10.04.1Copyright ASTM,100 Barr Harbor Drive,West Conshohocken,PA 19428-2959,United States.5.2.2 Stress relieved/annealed wire shall conform to therequirements of Table 7 for copper-modified gold wire,therequirements of Table 8 for beryllium-modified gold wire,tothe requirements of Table 9 for high-strength wire,and to therequirements of Table 10 for special purpose wire.NOTE3Hard wire is generally used for ultrasonic wire bonding.Annealed wire is used for thermocompression and thermoson