ASTM_F_847_-_94_1999.pdf

Designation:F 847 94(Reapproved 1999)Standard Test Methods forMeasuring Crystallographic Orientation of Flats on SingleCrystal Silicon Wafers by X-Ray Techniques1This standard is issued under the fixed designation F 847;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 These test methods cover the determination of a,theangular deviation between the crystallographic orientation ofthe direction perpendicular to the plane of a fiducial flat on acircular silicon wafer,and the specified orientation of the flat inthe plane of the wafer surface.1.2 These test methods are applicable for wafers with flatlength values in the range of those specified for silicon wafersin SEMI Specification M 1.They are suitable for use only onwafers with angular deviations of less than 65.1.3 The orientation accuracy achieved by these test methodsdepends directly on the accuracy with which the flat surfacecan be aligned with a reference fence and the accuracy of theorientation of the reference fence with respect to the X-raybeam.1.4 Two test methods are covered as follows:SectionsTest Method AX-Ray Edge Diffraction Method8 to 13Test Method BLaue Back Reflection X-Ray Method14 to 181.4.1 Test Method A is nondestructive and is similar to TestMethod A of Test Methods F 26 except that it uses specialwafer holding fixtures to orient the wafer uniquely with respectto the X-ray goniometer.The technique is capable of measur-ing the crystallographic direction of flats to a greater precisionthan the Laue back reflection method.1.4.2 Test Method B is also nondestructive,and is similar toTest Method E 82,and to DIN 50 433,Part 3,except that ituses“instant”film and special fixturing to orient the flat withrespect to the X-ray beam.Although it is simpler and morerapid,it does not have the precision of Test Method A becauseit uses less precise and less expensive fixturing and equipment.It produces a permanent film record of the test.NOTE1The Laue photograph may be interpreted to provide informa-tion regarding the crystallographic directions of wafer misorientation;however,this is beyond the scope of the present test method.Usersdesiring to carry out such interpretation should refer to Test Method E 82and to DIN 50 433,Part 3,or to a standard X-ray textbook.2,3Withdifferent wafer holding fixturing,Test Method B is also applicable todetermination of the orientation of a wafer surface.1.5 The values stated in inch-pound units are to be regardedas the standard.The values given in parentheses are forinformation only.1.6 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.For specific hazardstatements see Section 6.2.Referenced Documents2.1 ASTM Standards:E 82 Test Method for Determining the Orientation of aMetal Crystal4E 122 Practice for Choice of Sample Size to Estimate aMeasure of Quality for a Lot or Process5F 26 Test Methods for Determining the Orientation of aSemiconductive Single Crystal62.2Military Standard:MIL-STD-105D Sampling Procedures and Tables for In-spection by Attributes72.3Other Standards:Code of Federal Regulations,Title 10,Part 20,Standardsfor Protection Against Radiation8SEMI Specification M 1,Polished Monocrystalline SiliconSlices9DIN 50 433,Part 3,Testing of Materials for Semiconductor1These test methods are under the jurisdiction of ASTM Committee F01 onElectronics and are the direct responsibility of Subcommittee F01.06 on SiliconMaterials and Process Control.Current edition approved Aug.15,1994.Published October 1994.Originallypublished as F847 83.Last previous edition F847 87.2Wood,E.A.,Crystal Orientation Manual,Columbia University Press,NewYork,NY,1963.3Barret,C.S.,and Massalski,T.B.,The Structure of Metals,3rd editionMcGraw-Hill,New York,NY,1966.4Annual Book of ASTM Standards,Vol 03.01.5Annual Book of ASTM Standards,Vol 14.02.6Annual Book of ASTM Standards,Vol 10.05.7Available from Standardization Documents Order Desk,Bldg.4 Section D,700Robbins Ave.,Philadelphia,PA 19111-5094,Attn:NPODS.8Published in Federal Register,Nov.16,1960.Available from Superintendent ofDocuments,U.S.Government Printing Office,Washington,DC 20402.9Available from the Semiconductor Equipment and Materials Institute,Inc.,805E.Middlefield Rd.,Mountain View,CA 94043.1Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.Technology:Determining the Orientation of Single Crys-tals Using the Laue Back-Scattering Method6,103.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 orientationof a single crystal surface,the