ASTM_F_84_-_99.pdf

Designation:F 84 99Standard Test Method forMeasuring Resistivity of Silicon Wafers With an In-LineFour-Point Probe1This standard is issued under the fixed designation F 84;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(e)indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method2covers the measurement of theresistivity of silicon wafers with a in-line four-point probe.Theresistivity of a silicon crystal is an important materials accep-tance requirement.This test method describes a procedure thatwill enable interlaboratory comparisons of the room tempera-ture resistivity of silicon wafers.The precision that can beexpected depends on both the resistivity of the wafer and on thehomogeneity of the wafer.Round-robin tests have been con-ducted to establish the expected precision for measurements onp-type wafers with room temperature(23C)resistivity be-tween 0.0008 and 2000 Vcm and on n-type wafers withroom-temperature(23C)resistivity between 0.0008 and 6000Vcm.1.2 This test method is intended for use on single crystals ofsilicon in the form of circular wafers with a diameter greaterthan 16 mm(0.625 in.)and a thickness less than 1.6 mm(0.0625 in.).Geometrical correction factors required for thesemeasurements are available in tabulated form.31.3 This test method is to be used as a referee method fordetermining the resistivity of single crystal silicon wafers inpreference to Test Methods F 43.NOTE1The test method is also applicable to other semiconductormaterials but neither the appropriate conditions of measurement nor theexpected precision have been experimentally determined.Other geomet-rics for which correction factors are not available can also be measured bythis test method but only comparative measurements using similargeometrical conditions should be made in such situations.NOTE2DIN 504312is a similar,but not equivalent,method fordetermining resistivity.It is equivalent to Test Methods F 43.1.4 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.1.5 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.Specific hazardstatements are given in Section 8.2.Referenced Documents2.1 ASTM Standards:D 1193 Specification for Reagent Water4E 1 Specification for ASTM Thermometers5E 177 Practice for Use of the Terms Precision and Bias inASTM Test Methods6F 42 Test Methods for Conductivity Type of ExtrinsicSemiconducting Materials7F 43 Test Methods for Resistivity of Semiconductor Mate-rials7F 613 Test Method for Measuring Diameter of Semiconduc-tor Wafers72.2SEMI Standard:C1 Specifications for Reagents83.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 four-point probean electrical probe arrangement fordetermining the resistivity of a material in which separate pairsof contacts are used(1)for passing current through thespecimen and(2)measuring the potential drop caused by thecurrent.3.1.2 probe head,of a four-point probethe mounting that(1)fixes the positions of the four pins of the probe in a specificpattern such as an in-line(collinear)or square array and(2)contains the pin bearings and springs or other means forapplying a load to the probe pins.3.1.3 probe pin,of a four-point probeone of the four1This test method is under the jurisdiction of ASTM Committee F-1 onElectronics and is the direct responsibility of Subcommittee F01.06 on SiliconMaterials and Process Control.Current edition approved Dec.10,1999.Published February 2000.Originallypublished as F 84 67 T.Last previous edition F 84 98.2DIN 50431 is a similar,but not equivalent,method.It is the responsibility ofDIN Committee NMP 221,with which Committee F-1 maintains close liaison.DIN50431,Testing of Inorganic Semiconductor Materials:Measurement of the SpecificElectrical Resistance of Monocrystals of Silicon or Germanium by the Four-PointDirect-Current Technique with Linearly Arranged Probes,is available from BeuthVerlag GmbH Burggrafenstrasse 4-10,D-1000 Berlin 30,Federal Republic ofGermany.3Smits,F.M.,“Measurement of Sheet Resistivities with the Four-Point Probe”Bell System Technical Journal,BSTJA,Vol 37,1958,p.711:Swartzendruber,L.J.,“Correction Factor Tables for Four-Point Probe Resistivity Measurements on Thin,Circular Semiconductor Samples.”Technical Note 199,NBTNA,National Bureauof Standards,April 15,1964.4Annual Book of ASTM Standards,Vol 11.01.5Annual Book of ASTM Standards,Vol 14.03.6Annual Book of ASTM Standards,Vol 14.02.7Annual Book of ASTM Standards,Vol 10.05.8Available from the Semiconductor Equipment and Materials International,805East