ASTM E1438-11

Standard Guide for Measuring Widths of Interfaces in Sputter Depth Profiling Using SIMS

SIGNIFICANCE AND USE
Although it would be desirable to measure the extent of profile distortion in any unknown sample by using a standard sample and this guide, measurements of interface width (profile distortion) can be unique to every sample composition (1, 2, 3).3 This guide, that describes a method that determines the unique width of a particular interface for the chosen set of operating conditions. It is primarily intended to provide a method for checking on proper or consistent, or both, instrument performance. Periodic analysis of the same sample followed by a measurement of the interface width, in accordance with this guide, will provide these checks.
The procedure described in this guide is adaptable to any layered sample with an interface between layers in which a nominated element is present in one layer and absent from the other. It has been shown that for SIMS in particular (4, 5) and for surface analysis in general (6, 7), only rigorous calibration methods can determine accurate interface widths. Such procedures are prohibitively time-consuming. Therefore the interface width measurement obtained using the procedure described in this guide may contain significant systematic error (8). Therefore, this measure of interface width may have no relation to similar measures made with other methods. However, this does not diminish its use as a check on proper or consistent instrument performance, or both.
SCOPE
1.1 This guide provides the SIMS analyst with a method for determining the width of interfaces from SIMS sputtering data obtained from analyses of layered specimens. This guide does not apply to data obtained from analyses of specimens with thin markers or specimens without interfaces such as ion-implanted specimens.
1.2 This guide does not describe methods for the optimization of interface width or the optimization of depth resolution.
This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 31-Oct-2011
• ICS: 29.045 - Semiconducting materials
• Technical Committee: E42 - Surface Analysis
• Drafting Committee: E42.06 - SIMS

Relations

• Replaces: ASTM E1438-06 - Standard Guide for Measuring Widths of Interfaces in Sputter Depth Profiling Using SIMS
• Effective Date: 01-Nov-2011
• Replaced By: ASTM E1438-11(2019) - Standard Guide for Measuring Widths of Interfaces in Sputter Depth Profiling Using SIMS
• Effective Date: 01-Nov-2019

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:E1438 −11
Standard Guide for
Measuring Widths of Interfaces in Sputter Depth Profiling
1
Using SIMS
This standard is issued under the fixed designation E1438; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope an ion beam of a particular ion species, ion energy, and angle
of incidence is used to bombard a sample.The beam is rastered
1.1 This guide provides the SIMS analyst with a method for
or defocused so as to attempt to produce uniform current
determining the width of interfaces from SIMS sputtering data
density in the analyzed area, that is defined by means of
obtained from analyses of layered specimens (both organic and
mechanical or electronic gating. The intensity of one or more
inorganic). This guide does not apply to data obtained from
secondary ions is monitored with respect to time as sputtering
analyses of specimens with thin markers or specimens without
continues.
interfaces such as ion-implanted specimens.
4.2 The interface width is then determined from the second-
1.2 This guide does not describe methods for the optimiza-
ary ion intensity versus time data according to an arithmetic
tion of interface width or the optimization of depth resolution.
model described in the Procedure section. A measurement of
1.3 This standard does not purport to address all of the
the thickness of the layer overlying the interface is required.
safety concerns, if any, associated with its use. It is the
This measurement may be performed by another analytical
responsibility of the user of this standard to establish appro-
technique.
priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use.
5. Significance and Use
5.1 Although it would be desirable to measure the extent of
2. Referenced Documents
profile distortion in any unknown sample by using a standard
2
2.1 ASTM Standards:
sample and this guide, measurements of interface width (pro-
E673 Terminology Relating to SurfaceAnalysis (Withdrawn
file distortion) can be unique to every sample composition (1,
3
4
2012)
2). This guide, describes a method that determines the unique
width of a particular interface for the chosen set of operating
3. Terminology
conditions. It is intended to provide a method for checking on
3.1 Definitions:
proper or consistent, or both, instrument performance. Periodic
3.1.1 SeeTerminology E673 for definitions of terms used in
analysis of the same sample followed by a measurement of the
SIMS.
interface width, in accordance with this guide, will provide
these checks.
4. Summary of Guide
5.2 The procedure described in this guide is adaptable to
4.1 This guide will allow interface widths to be calculated
any layered sample with an interface between layers in which
fromplotsofSIMSsecondaryionintensityversustimethatare
anominatedelementispresentinonelayerandabsentfromthe
acquired during sputtering of layered specimens. It assumes
other. It has been shown that for SIMS in particular (3, 4) and
that a primary ion beam with a stable current density is being
for surface analysis in general (5, 6), only rigorous calibration
used. Briefly, these plots are obtained in the following fashion:
methods can determine accurate interface widths. Such proce-
dures are prohibitively time-consuming. Therefore the inter-
face width measurement obtained using the procedure de-
1
This guide is under the jurisdiction of ASTM Committee E42 on Surface
scribed in this guide may contain significant systematic error
Analysis and is the direct responsibility of Subcommittee E42.06 on SIMS.
Current edition approved Nov. 1, 2011. Published December 2011. Originally
(7). Therefore, this measure of interface width may have no
approved in 1991. Last previous edition approved in 2006 as E1438 – 06. DOI:
relation to similar measures made with other methods.
10.1520/E1438-11.
However, this does not diminish its use as a check on proper or
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM consistent instrument performance, or both.
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website.
3 4
The last approved version of this historical standard is referenced on The boldface numbers given in parentheses refer to a list of references at the
www.astm.org. end of this guide.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

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E1438−11
5.3 Thisguidecanbeusedfor
...

This document is not anASTM standard and is intended only to provide the user of anASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation:E1438–06 Designation: E1438 – 11
Standard Guide for
Measuring Widths of Interfaces in Sputter Depth Profiling
1
Using SIMS
This standard is issued under the fixed designation E1438; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This guide provides the SIMS analyst with a method for determining the width of interfaces from SIMS sputtering data
obtained from analyses of layered specimens (both organic and inorganic). This guide does not apply to data obtained from
analyses of specimens with thin markers or specimens without interfaces such as ion-implanted specimens.
1.2 This guide does not describe methods for the optimization of interface width or the optimization of depth resolution.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory
limitations prior to use.
2. Referenced Documents
2
2.1 ASTM Standards:
E673 Terminology Relating to Surface Analysis
3. Terminology
3.1 Definitions:
3.1.1 See Terminology E673 for definitions of terms used in SIMS.
4. Summary of Guide
4.1 This guide will allow interface widths to be calculated from plots of SIMS secondary ion intensity versus time that are
acquired during sputtering of layered specimens. It assumes that a primary ion beam with a stable current density is being used.
Briefly,theseplotsareobtainedinthefollowingfashion:anionbeamofaparticularionspecies,ionenergy,andangleofincidence
isusedtobombardasample.Thebeamisrasteredordefocusedsoastoattempttoproduceuniformcurrentdensityintheanalyzed
area, that is defined by means of mechanical or electronic gating. The intensity of one or more secondary ions is monitored with
respect to time as sputtering continues.
4.2 The interface width is then determined from the secondary ion intensity versus time data according to an arithmetic model
described in the Procedure section. A measurement of the thickness of the layer overlying the interface is required. This
measurement may be performed by another analytical technique.
5. Significance and Use
5.1 Althoughitwouldbedesirabletomeasuretheextentofprofiledistortioninanyunknownsamplebyusingastandardsample
3
and this guide, measurements of interface width (profile distortion) can be unique to every sample composition (1, 2, 32). This
guide, that describes a method that determines the unique width of a particular interface for the chosen set of operating conditions.
It is primarily intended to provide a method for checking on proper or consistent, or both, instrument performance. Periodic
analysis of the same sample followed by a measurement of the interface width, in accordance with this guide, will provide these
checks.
5.2 The procedure described in this guide is adaptable to any layered sample with an interface between layers in which a
nominated element is present in one layer and absent from the other. It has been shown that for SIMS in particular (43, 54) and
forsurfaceanalysisingeneral(65,76),onlyrigorouscalibrationmethodscandetermineaccurateinterfacewidths.Suchprocedures
1
This guide is under the jurisdiction of ASTM Committee E42 on Surface Analysis and is the direct responsibility of Subcommittee E42.06 on SIMS.
Current edition approved Nov. 1, 2006.2011. Published November 2006.December 2011. Originally approved in 1991. Last previous edition approved in 20012006 as
E1438–91(2001).E1438 – 06. DOI: 10.1520/E1438-06.10.1520/E1438-11.
2
For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
3
The boldface numbers given in parentheses refer to a list of references at the end of this guide.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
1

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E1438 – 11
are prohibitively time-consuming.Therefore the interface width measurement obtained using the procedure described in this guide
may contain significant systematic error (87). Therefore, this measure of interface width m
...