ASTM_F_638_-_88_2001.pdf

Designation:F 638 88(Reapproved 2001)Standard Specification forFine Aluminum1%Magnesium Wire for SemiconductorLead-Bonding1This standard is issued under the fixed designation F 638;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 This specification covers aluminum-1%magnesium al-loy wire for internal connections in semiconductor devices andis limited to wires of diameter up to and including 0.002 in.(0.051 mm).For diameters larger than 0.0020 in.(0.051 mm),the specifications are to be agreed upon between the purchaserand the supplier.1.2 The values stated in inch-pound units are to be regardedas the standard.The values stated in parentheses are forinformation only.2.Referenced Documents2.1 ASTM Standards:F 16 Test Methods for Measuring Diameter or Thickness ofWire and Ribbon for Electronic Devices and Lamps2F 72 Specification for Gold Wire for Semiconductor LeadBonding2F 205 Test Method for Measuring Diameter of Fine Wire byWeighing2F 219 Test Methods of Testing Fine Round and Flat Wirefor Electron Devices and LampsF 584 Practice for Visual Inspection of Semiconductor LeadBonding Wire22.2Military Standard:MIL-STD-105 Sampling Procedures and Tables for Inspec-tion by Attributes33.Ordering Information3.1 Orders for material under this specification shall includethe following information:3.1.1 Quantity,3.1.2 Composition(see Section 7),3.1.3 Size(diameter)(see Section 5),3.1.4 Breaking load and elongation(see Section 4),3.1.5 Spooling,packaging,and marking(see Section 11),3.1.6 Buyer part number,and3.1.7 Special requirements such as for certificate of compli-ance(see Section 10).4.Physical Requirements4.1 Elongation and breaking load ranges for the wire shallbe specified by the purchaser.The maximum ranges of themechanical properties are listed in Table 1.4.2 Mechanical property requirements in ranges smallerthan those listed in Table 1 may be specified upon agreementbetween the purchaser and the supplier.NOTE1The nature of aluminum-1%magnesium alloy is such that themechanical properties of both as-drawn and annealed wires overlapconsiderably.It is also possible to vary the properties of the hard wire bychanging manufacturing parameters and procedures.For these reasons,nodistinction is made in this specification between the two types.5.Dimensions,Weights,and Permissible Variations5.1 Wire size shall be expressed as wire diameter in decimalfractions of an inch(or millimetres)or as weight per unitlength.5.2 Tolerances for various size ranges are specified in Table2.5.3 When wire size is expressed in terms of weight,thefollowing values shall be used:5.3.1 Density of Aluminum-1%Magnesium2.7 g/cm35.3.2 Weight of a 200-mm Length of Wire 0.0254 mm inDiameter0.274 mg.6.Surface Finish6.1 The wire surface shall be clean and free of finger oils,lubricant residues,stains,and particulate matter.6.2 Mechanical damage to the wire surface such as nicks,scratches,and kinks shall be held to a minimum.6.3 The nature and the extent of defects permitted to bepresent on the surface of the wire shall be agreed between thesupplier and the purchaser.1This specification is under the jurisdiction of ASTM Committee F01 onElectronics and is the direct responsibility of Subcommittee F 01.07 on Intercon-nection Bonding Carrier Bonding.Current edition approved May 27,1988.Published July 1988.Originallypublished as F 638 82.Last previous edition F 638 82.2Annual Book of ASTM Standards,Vol 10.04.3Available from Standardization Documents Order Desk,Bldg.4 Section D,700Robbins Ave.,Philadelphia,PA 19111-5094,Attn:NPODS.1Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.7.Chemical Requirements7.1 The alloy composition shall be 1.00 6 0.15%magne-sium and between 98.84 and 99.15%aluminum.All otherelements are considered impurities.7.2 No single impurity shall exceed 0.0050%,and the totalof all detectable impurities shall not exceed 0.01%.7.3 Any lower or higher impurity content shall be as agreedupon between the purchaser and the supplier as part of thepurchase contract.8.Sampling8.1 Unless otherwise agreed upon between the purchaserand the supplier,conformance with Section 4 shall be deter-mined by MIL-STD-105.9.Test Methods9.1 Elongation and Breaking LoadTest Methods F 219.9.2 Dimensional MeasurementDetermine the wire diam-eter by one of the following methods:9.2.1 Measure the diameter indirectly by weighing in accor-dance with Test Method F 205.9.2.2 Measure the diameter by the direct-contact method(for example,compressing wire between preloaded anvilswhose separation is indicated on a micrometer scale)agreedupon between the purchaser and the supplier.NOTE2The procedures of Test Methods F 16 may be applicable insome instances.Use of Test