ASTM F487-13

Designation: F487 − 13Standard Specification forFine Aluminum–1 % Silicon Wire for Semiconductor Lead-Bonding1This standard is issued under the fixed designation F487; the number immediately following the designation indicates the year of originaladoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscriptepsilon (´) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification covers aluminum–1 % silicon alloywire for internal connections in semiconductor devices and islimited to wire of diameter up to and including 76 µm (0.003in.). For diameters larger than 76 µm (0.003 in.), the specifi-cations are to be agreed upon between the purchaser and thesupplier.1.2 The values stated in SI units are to be regarded as thestandard, regardless of whether they appear first or second in atable. Values given in parentheses are for information only.2. Referenced Documents2.1 ASTM Standards:2F16 Test Methods for Measuring Diameter or Thickness ofWire and Ribbon for Electronic Devices and LampsF219 Test Methods of Testing Fine Round and Flat Wire forElectron Devices and Lamps2.2 Military Standard:3MIL-STD-105 Sampling Procedures and Tables for Inspec-tion by Attributes3. Ordering Information3.1 Orders for material under this specification shall includethe following information:3.1.1 Quantity,3.1.2 Size (see Section 5),3.1.3 Breaking load and elongation (see Section 4),3.1.4 Packaging and marking (see Section 11), and3.1.5 Special requirements, such as for certificate of com-pliance (see Section 10).4. Physical Requirements4.1 Elongation and breaking-load ranges for the wire shallbe specified by the purchaser. The maximum ranges of thesemechanical 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.NOTE 1—The nature of aluminum–1 % silicon alloy is such that themechanical properties of both as-drawn and annealed wires overlapconsiderably. It is also possible to alter the properties of hard wire byvarying the manufacturing parameters and procedures. For these reasons,no distinction is made between the two types of wire in this specification.5. Dimensions, Weights, and Permissible Variations5.1 Wire size shall be expressed in terms of wire diameter indecimal fractions of millimetres (inches). Tolerances for vari-ous size ranges are specified in Table 2.5.2 When wire size is expressed in terms of weight, thefollowing values shall be used:5.2.1 Density of Aluminum–1 % Silicon—2.7 g/cm3.5.2.2 Weight of a 200-mm Length of Wire 25.4 µm inDiameter—0.274 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 inspection shall be carried out by electronic, optical,or other inspection method is agreed upon between thepurchaser and the supplier. The nature and extent of defectspermitted to be present on the surface of the wire shall beagreed upon between the purchaser and the supplier.7. Chemical Requirements7.1 The alloy composition shall be 1.00 6 0.15 % silicon,and between 98.84 and 99.15 % aluminum. All other elementsare considered impurities.7.2 No single impurity shall exceed 0.0050 % and the totalof all detectable impurities shall not exceed 0.01 %.1This specification is under the jurisdiction of ASTM Committee F01 onElectronics and is the direct responsibility of Subcommittee F01.03 on MetallicMaterials, Wire Bonding, and Flip Chip.Current edition approved Jan. 1, 2013. Published January 2013. Originallyapproved in 1977. Last previous edition approved in 2006 as F487 – 88 (2006).DOI: 10.1520/F0487-13.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at service@astm.org. For Annual Book of ASTMStandards volume information, refer to the standard’s Document Summary page onthe ASTM website.3Available from Standardization Documents Order Desk, Bldg. 4 Section D, 700Robbins Ave., Philadelphia, PA 19111-5094, Attn: NPODS.Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States17.3 Any lower or higher impurity content shall be as agreedupon between the purchaser and the supplier as part of thepurchase contract.7.4 Larger aluminum wire diameters often include nickel orother impurities or both to minimize corrosion in plasticpackages. Such wire is not covered by this specification.8. Sampling8.1 Unless otherwise agreed upon by the purchaser and thesupplier, conformance with Section 4 shall be determined byMIL-STD-105.9. Test Methods9.1 Elongation and Breaking Load —Determine elongationand breaking load in accordance with Test Methods F219.9.2 Dimensional Measurement—Determine the wire diam-eter by one of the following methods:9.2.1 Measure the diameter directly in accordance with TestMethods F16.9.2.2 Measure the diameter by optical means agreed uponbetween the purchaser and the supplier.NOTE 2—Optical methods for measuring wire diameter are underdevelopment by Committee F-1 on Electronics.9.3 Chemical Analysis—Verify that the chemical require-ments are satisfied by means of spectrographic analysis orother means agreed upon between the purchaser and thesupplier.10. Certification10.1 When agreed upon in writing by the purchaser and thesupplier, a certification shall be made the basis of acceptance ofthe material. This shall consist of a copy of the manufacturer’stest report or a statement by the supplier, accompanied by acopy of the test results, that the material has been sampled,tested, and inspected in accordance with the provisions of thisspecification. Each certification so furnished shall be signed byan authorized agent of the supplier or the manufacturer.11. Packaging (Spooling) and Package Marking11.1 The type of spool shall be specified as agreed uponbetween the purchaser and the supplier. (For aging propertiessee the shelf life aging test, in Appendix X1.)NOTE 3—Types of spools recommended for fine lead-bonding wire willbe agreed upon by purchaser and manufacturer that are compliant with theuser’s intended bonding machines.11.2 The maximum and minimum length of wire on a spoolshall be as specified by the purchaser.11.3 The wire shall be wound so that it despools freely andwill be free of kinks and nicks. Spools shall be free of nicks,burrs, and dents. The beginning and end of the wind shall beclearly identified. The method of termination shall be as agreedupon between the purchaser and the supplier.11.4 The wire shall be protected against damage in normalhandling and shipping. The outer container shall bear markingsindicating“ fragile” contents and designating the proper end tobe “up” in order to maintain spool axes horizontal duringshipping. The outer container shall also be marked “Extremesof Temperature Must Be Avoided.”NOTE 4—Other package marking should be specified by the purchaserif required.11.5 The basic packing unit shall be legibly marked with thefollowing information:11.5.1 Material description,11.5.2 Diameter, in. (or mm),11.5.3 Length, metres (or feet),11.5.4 Elongation and breaking-load specifications,11.5.5 Melt or bar number,11.5.6 Date of packaging,11.5.7 User’s part number, and11.5.8 Manufacturer’s name and product designation, if any.12. Keywords12.1 silicon aluminum wire; wire bondingTABLE 1 Typical Elongation and Breaking Load ofAluminum–1 % Silicon Alloy WireNOTE 1—Select the desired nominal breaking load and elongation forthe wire by specifying a range of mechanical properties that includes thedesired values.ANominal Diameter,in. (mm)Breaking Load, g Elongation, %Min MaxMaxRangeBMin MaxMaxRangeC0.0007 (0.018) 3 12 2 0.5 3.0 2.00.0010 (0.025) 12 22 3 0.5 4.0 2.50.0012 (0.030) 14 30 3 0.5 4.0 2.50.00125 (0.032) 15 32 3 0.5 4.0 3.00.0015 (0.038) 20 50 4 0.5 4.0 3.00.0020 (0.051) 32 90 6 1.0 4.0 3.0AExample: Wire of 25-µm (0.001-in.) diameter with a breaking load of 16 g and anelongation of 2.0 % is desired. Specify a breaking-load range of 14 to 18 g (16 ±2 g) and an elongation range of 1.0 to 3.5 % (2.0 + 1.5 %, 2.0 − 1.0 %). (Note—Smaller ranges are acceptable; for this example, ranges of 15 to 17 g and 1.0 to3.0 % could be specified. For diameters larger than 0.0020 in. (0.051 mm), thespecifications are to be agreed upon between the purchaser and the supplier.)BA range of permissible breaking strength of no more than the number of gramsshown shall be selected from within the overall range designated by the minimumand maximum values for the given diameter.CA range of permissible elongation of no more than the number of percentagepoints shown shall be selected from within the overall range designated by theminimum and maximum values for the given diameter.TABLE 2 Dimensional TolerancesNominal Diameter, in. (mm)DiameterTolerance, % ofnominalWeightTolerance, % ofnominal0.0005 to 0.0020 (0.013 to 0.051), incl ± 3 ± 6F487 − 132APPENDIX(Nonmandatory Information)X1. SHELF LIFE AGING TEST 1983–1985X1.1 PurposeX1.1.1 To determine the effect of room temperature agingon the stress-strain characteristics of bonding wires of severalcompositions and tempers.X1.2 Test parametersX1.2.1 Environment—Typical stock room, 22.8 6 1.7°C(73 6 3°F).X1.2.2 Spooling—2-in. diameter, Aluminum, 100 ft/spool.X1.2.3 Instrument—Instron type, 1 in./min., 10 in. length.X1.2.4 Sampling—Average of five readings per notation.X1.2.5 Time—Intervals shown on charts, see Fig. X1.1.X1.2.6 Wire Size—All specimens, 25-µm (0.001-in.)diameter.NOTE 1—These data were taken in the 1980s. However, the metal-lurgy of 2012 Al-Si wire is unchanged and the data are consideredcorrect for this purpose today.FIG. X1.1 Aging Chart 1 % Silicon Aluminum Bonding Wire AlloyF487 − 133ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.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 International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. 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