ASTM_F_1512_-_94_2011.pdf

Designation:F151294(Reapproved 2011)Standard Practice forUltrasonic C-Scan Bond Evaluation of SputteringTarget-Backing Plate Assemblies1This standard is issued under the fixed designation F1512;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()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This practice describes a method for ultrasonic mappingof the soundness of a bond joining a sputtering target to itssupporting backing plate.The results of the examination maybe used in predicting the target-backing plate assemblyssuitability for use.Accept/reject standards are not specified;these are subject to agreement between target supplier and user,depending upon the application requirements.1.2 This standard is intended to be used with PracticeE1001.1.3 The method reveals unbonded areas 0.125 in.(3 mm)indiameter and larger.The technique permits,for example,unambiguous quantitative measurement of the voided area insolder bonds.1.3.1 This technique may also show regions in which bondintegrity is marginally degraded by imperfect adhesion,forexample,areas in which oxide inclusion has inhibited thedevelopment of full bond strength.Evaluation of indications ofdegraded bond areas may vary in rigor from purely subjectiveto semiquantitative.Target supplier and user must agree uponthe means used to display and grade partially bonded areas.1.4 This practice is applicable to assemblies having planarbonds in which the design provides at least one flat planeparallel to the bond that may be used as the entry/exit surfacefor ultrasonic excitation.1.5 Only the immersion pulse-echo method is covered.1.6 Evaluation by this method is intended to be nondestruc-tive.For target assemblies that would be degraded by immer-sion in demineralized water,for example,for porous targetmaterials,the test should be considered a destructive one.1.7 This practice is applicable to bonding methods that usea filler material to join the target and backing plate.Theseinclude solder,epoxy,and braze bonds.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:2E127 Practice for Fabricating and Checking Aluminum Al-loy Ultrasonic Standard Reference BlocksE428 Practice for Fabrication and Control of Metal,Otherthan Aluminum,Reference Blocks Used in UltrasonicTestingE1001 Practice for Detection and Evaluation of Discontinui-ties by the Immersed Pulse-Echo Ultrasonic MethodUsing Longitudinal WavesE1316 Terminology for Nondestructive Examinations2.2 American Society for Nondestructive Testing Standard:ASNT Recommended Practice SNT-TC-1A for PersonnelQualification and Certification in Nondestructive Testing33.Terminology3.1 Definitions:3.1.1 For definitions of terms used in this practice seePractice E1001 and Terminology E1316.4.Summary of Practice4.1 This practice describes a preferred means of applyingPractice E1001 to obtain a two dimensional map of the flaws ina sputtering target-backing plate bond.The target-backing plateassembly is immersed in demineralized water,used as acouplant,and the target-backing plate joint is scanned ultra-sonically.1This practice is under the jurisdiction of ASTM Committee F01 on Electronicsand is the direct responsibility of Subcommittee F01.17 on Sputter Metallization.Current edition approved June 1,2011.Published June 2011.Originallyapproved in 1994.Last previous edition approved in 2003 as F151294(2003).DOI:10.1520/F1512-94R11.2For 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.3Available fromAmerican Society for Nondestructive Testing(ASNT),P.O.Box28518,1711 Arlingate Ln.,Columbus,OH 43228-0518,http:/www.asnt.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.Significance and Use5.1 This practice supplements Practice E1001 by indicatingspecific equipment choices and test arrangements appropriatefor evaluating sputtering target bonds.5.2 The bond between sputtering target and its supportingbacking plate is a critical reliability element in a sputterdeposition system.A bond must have high thermal conductiv-ity to provide adequate target cooling during sputtering.Thetarget-backing plate joint must also have str