ASTM_F_458_-_13.pdf

Designation:F45813Standard Practice forNondestructive Pull Testing of Wire Bonds1,2This standard is issued under the fixed designation F458;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()indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope1.1 This practice covers nondestructive testing of individualwire bonds made by either ultrasonic,thermal compression orthermosonic techniques.The test is intended to reveal(bybreaking)nonacceptable wire bonds but is designed to avoiddamage to acceptable wire bonds.NOTE1Common usage at the present time considers the term“wirebond”to include the entire interconnection:both welds and the interven-ing wire span.1.2 The practice covers wire bonds made with small-diameter(from 0.0007 to 0.003-in.(18 to 76-m)wire such asthe type used in integrated circuits and hybrid microcircuits,system in package,and so forth.1.3 This practice can be used only when the loop height ofthe wire bond is large enough to allow a suitable hook forpulling to be placed under the wire.1.4 While the procedure is applicable to wire of anycomposition and metallurgical state,criteria are given only forgold and aluminum wire.1.5 Adestructive pull test is used on wire bonds of the sametype and geometry to provide the basis for the determination ofthe nondestructive pulling force to be used in this practice.Thismay only be used if the sample standard deviation,s,of thepulling forces required to destroy at least 25 of the same wirebonds tested by the destructive pull-test method is less than orequal to 0.25 of the sample average,x.If s 0.25 x,thispractice may not be used.NOTE2If s 0.25 x,some aspect of the bonding process is out ofcontrol.Following corrective action,the destructive pull-test measure-ments should be repeated to determine if the s 0.25 x criterion is met.1.6 The nondestructive wire-bond pull test is to be per-formed before any other treatment or screening followingbonding and at the same point in processing as the accompa-nying destructive test.Preferably,this is done immediatelyafter bonding.1.7 The procedure does not ensure against wire-bond failuremodes induced after the test has been performed.1.8 The values stated in inch-pound units are to be regardedas standard.The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.9 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:3F459 Test Methods for Measuring Pull Strength of Micro-electronic Wire Bonds2.2 Military Standard:4MIL-STD-883 Method 20233.Summary of Practice3.1 The use of nondestructive wire-bond pull tests is predi-cated on data obtained from destructive pull tests on typicalsamples selected from a lot.The maximum safe nondestructivepull-force levels are determined as a function of the metallur-gical properties of the wire and from the calculated mean(x)and standard deviation(s)of the destructive pull-test datadetermined in accordance with Test Methods F459.3.2 In some cases,rather than use a calculated nondestruc-tive pull force,a fixed pull force may be agreed upon by testparticipants.This value may be based upon industry practice,or some other accepted value,such as that in MIL STD 883,Method 2023.All other parts of the present ASTM standardwill apply.1This practice is under the jurisdiction of ASTM Committee F01 on Electronicsand is the direct responsibility of Subcommittee F01.03 on Metallic Materials,WireBonding,and Flip Chip.Current edition approved Jan.1,2013.Published January 2013.Originallyapproved in 1976 as F458 76 T.Last previous edition approved in 2006 as F458 06.DOI:10.1520/F0458-13.2This procedure,with current status and limitations,was published in:Harman,G.G.,Wire Bonding in Microelectronics,3rd Edition,McGraw Hill,2010,Appendix 4B.2.3For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.4Available from Standardization Documents Order Desk,Bldg.4 Section D,700Robbins Ave.,Philadelphia,PA 191115094,Attn:NPODS.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.3 The maximum safe nondestructive bond-pull force isthen applied as a screen for individual wire bonds to identify allbonds with pull strength below the predetermined level ofacceptability.4.Significa