ASTM E1634-11(2019)

Standard Guide for Performing Sputter Crater Depth Measurements

SIGNIFICANCE AND USE
4.1 Sputter crater depth measurements are performed in order to determine a sputter rate (depth/time) for each matrix sputtered during a sputter depth profile or similar in-depth type analyses. From sputter rate values, a linear depth scale can be calculated and displayed for the sputter depth profile.  
4.2 Data obtained from surface profilometry are useful in monitoring instrumental parameters (for example, raster size, shape, and any irregularities in topography of the sputtered crater) used for depth profiles.
SCOPE
1.1 This guide covers the preferred procedure for acquiring and post-processing of sputter crater depth measurements. This guide is limited to stylus-type surface profilometers equipped with a stage, stylus, associated scan and sensing electronics, video system for sample and scan alignment, and computerized system.  
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 31-Oct-2019
• ICS: 71.040.50 - Physicochemical methods of analysis
• Technical Committee: E42 - Surface Analysis
• Drafting Committee: E42.06 - SIMS

Relations

• Replaces: ASTM E1634-11 - Standard Guide for Performing Sputter Crater Depth Measurements
• Effective Date: 01-Nov-2019
• Refers: ASTM E673-03 - Standard Terminology Relating to Surface Analysis (Withdrawn 2012)
• Effective Date: 01-Dec-2003
• Refers: ASTM E673-02a - Standard Terminology Relating to Surface Analysis
• Effective Date: 10-Dec-2002
• Refers: ASTM E673-01 - Standard Terminology Relating to Surface Analysis
• Effective Date: 10-Nov-2001
• Refers: ASTM E673-98E1 - Standard Terminology Relating to Surface Analysis
• Effective Date: 10-Nov-2001
• Referred By: ASTM E1127-08(2015) - Standard Guide for Depth Profiling in Auger Electron Spectroscopy
• Effective Date: 01-Nov-2019
• Referred By: ASTM E2735-14(2020) - Standard Guide for Selection of Calibrations Needed for X-ray Photoelectron Spectroscopy (XPS) Experiments
• Effective Date: 01-Nov-2019

Overview

ASTM E1634-11(2019), "Standard Guide for Performing Sputter Crater Depth Measurements," provides a comprehensive methodology for acquiring and analyzing sputter crater depth using stylus-type surface profilometers. Developed by ASTM International, this guide is essential for laboratories and research facilities performing depth profile analyses, particularly in surface analysis applications such as Auger electron spectroscopy (AES), secondary ion mass spectrometry (SIMS), and X-ray photoelectron spectroscopy (XPS).

By standardizing procedures for measuring and post-processing crater depths, ASTM E1634 helps ensure the accuracy and reproducibility of sputter rate calculations, instrumental parameter monitoring, and the establishment of a linear depth scale in sputter depth profiling.

Key Topics

• Surface Profilometry: The guide emphasizes the use of stylus-type surface profilometers equipped with essential components like a stage, stylus, scanning electronics, and video alignment systems.
• Measurement Procedure: Detailed steps are provided for acquiring crater depth measurements after sputtering, including marking the crater, sample handling, and scan alignment.
• Instrument Settings: Recommendations include selection of:
  • Stylus type and radius
  • Stylus force suitable for material type
  • Scan speed and scan length
  • Number of scans for signal averaging
• Post-Processing: The standard describes the interpretation of results, including data leveling, rescaling, zeroing surface depth, and averaging surface measurements for accurate depth determination.
• Large-Area Craters: Modified procedures are introduced for craters created by large-diameter ion beams, often used in advanced surface analysis techniques.
• Precision and Accuracy: Guidance is given for evaluating measurement precision (by repeated scans) and accuracy (by using calibrated depth standards and considering instrument calibration and setup).

Applications

ASTM E1634 is widely applicable in fields requiring precise surface analysis and depth profiling, such as:

• Material Science Research: Determining coating thickness, layer uniformity, and material composition gradients.
• Semiconductor Industry: Profiling thin films and interfaces in microelectronics and MEMS devices.
• Surface Engineering: Analyzing wear, corrosion, or surface treatments by measuring depth of sputtered or altered regions.
• Analytical Chemistry: Supporting quantification in XPS, AES, and SIMS by associating sputter time with physical depth.
• Instrumentation Calibration: Routine instrument verification and method validation in quality assurance programs.

By following ASTM E1634, practitioners can ensure reliable and consistent sputter depth measurements, optimizing analytical outcomes and supporting data comparability across laboratories.

Related Standards

ASTM E1634 aligns with other key standards in the field of surface analysis and material characterization, including:

• ASTM E673: Terminology Relating to Surface Analysis (note: withdrawn in 2012, but referenced for legacy definitions)
• ISO Surface Profilometry Standards: For broader guidance on profilometer use and results interpretation
• Instrument Manufacturer Protocols: Complementary to proprietary application notes for stylus profilometers
• Other ASTM Surface Analysis Guides: Covering additional analytical methods, sputtering protocols, and calibration techniques

For the latest details and supplementary documents, visit the ASTM Standards Database or consult with equipment providers for up-to-date application support.

---

Keywords: sputter crater depth measurement, stylus surface profilometry, surface analysis standard, ASTM E1634, sputter depth profiling, thin film analysis, X-ray photoelectron spectroscopy, SIMS, AES, profilometer calibration

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: E1634 −11 (Reapproved 2019)
Standard Guide for
Performing Sputter Crater Depth Measurements
This standard is issued under the fixed designation E1634; 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 4. Significance and Use
1.1 This guide covers the preferred procedure for acquiring 4.1 Sputter crater depth measurements are performed in
and post-processing of sputter crater depth measurements.This order to determine a sputter rate (depth/time) for each matrix
guide is limited to stylus-type surface profilometers equipped sputtered during a sputter depth profile or similar in-depth type
with a stage, stylus, associated scan and sensing electronics, analyses. From sputter rate values, a linear depth scale can be
videosystemforsampleandscanalignment,andcomputerized calculated and displayed for the sputter depth profile.
system.
4.2 Data obtained from surface profilometry are useful in
1.2 The values stated in SI units are to be regarded as monitoring instrumental parameters (for example, raster size,
standard. No other units of measurement are included in this shape, and any irregularities in topography of the sputtered
standard. crater) used for depth profiles.
1.3 This standard does not purport to address all of the
5. General Procedure
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
5.1 Upon completing a sputter depth profile, mark the crater
priate safety, health, and environmental practices and deter-
for future identification (one can mark the exterior corner(s) of
mine the applicability of regulatory limitations prior to use.
a crater with features, for example, lines, holes, etc., produced
1.4 This international standard was developed in accor-
using an unrastered ion beam). Note the crater orientation with
dance with internationally recognized principles on standard-
respect to the other sample features
ization established in the Decision on Principles for the
5.2 Placethesampleontheprofilometerstagesurface.Ifthe
Development of International Standards, Guides and Recom-
sample has an area of less than 1 cm , mount the sample onto
mendations issued by the World Trade Organization Technical
another larger flat surface to prevent sample movement when
Barriers to Trade (TBT) Committee.
profilometry is performed. The system should be reasonably
leveled; for details on instrumental adjustments, see manufac-
2. Referenced Documents
turer’s operating manual(s). Keep the environment as dust-free
2.1 ASTM Standards: as possible and dust-off the sample surface with a clean air/gas
E673 Terminology Relating to SurfaceAnalysis (Withdrawn
jet before performing the measurement.
2012)
5.3 Pre-select surface profilometer operational settings;
computerized models are commonly used. Most surface profi-
3. Terminology
lometers commonly permit selection of the following param-
3.1 Definitions:
eters:
3.1.1 Terms used in surface analysis are defined in Termi-
5.3.1 Stylus type (for example, diamond stylus).
nology E673.
5.3.2 Stylus radius (for example, 5 µm; various stylus radii
are available depending upon desired resolution of
measurement, and to a certain degree the strength of the stylus
1 tip for varying hardness of materials).
This guide is under the jurisdiction of ASTM Committee E42 on Surface
Analysis and is the direct responsibility of Subcommittee E42.06 on SIMS.
5.3.3 Stylus force (that is, force exerted on the analytical
Current edition approved Nov. 1, 2019. Published November 2019. Originally
sample during operation, for example, 15 mg; this is an
approved in 2002. Last previous edition approved in 2011 as E1634 – 11. DOI:
important variable when profiling a sample with high hardness
10.1520/E1634-11R19.
levels; damage to the stylus may occur, and hence damage to
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
the instrumentation or errors in profilometry measurements, or
Standards volume information, refer to the standard’s Document Summary page on
both, may result), similarly, excessive force can damage soft
the ASTM website.
samples such as polymers or photoresists and result in errone-
The last approved version of this historical standard is referenced on
www.astm.org. ous measurements.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E1634 − 11 (2019)
5.3.4 Scan speed (for example, 50 µm/s; this value is
dependent upon permissible noise levels, accuracy, etc., and is
typically determined experimentally).
5.3.5 Scan length (one typically uses twice the crater size to
allow for scanning over the level areas about the sputtered
crater.
5.3.6 Number of scans for signal averaging (for example,
three repetitive scans averaged to improve the signal-to-noise
ratio).
5.4 Lower the stylus in an area outside the sputtered crater,
atadistancefromthecra
...