GB/T 17722-2026 Microbeam analysis—Method for thickness measurement on goldcoating layer by SEM English, Anglais, Englisch, Inglés, えいご
This is a draft translation for reference among interesting stakeholders. The finalized translation (passing through draft translation, self-check, revision and verification) will be delivered upon being ordered.
ICS 13.220.10
CCS H 57
National Standard of the People's Republic of China
GB/T 17722-2026
Replaces GB/T 17722-1999
Microbeam analysis - Method for thickness measurement on goldcoating layer by SEM
微束分析 金覆盖层厚度的扫描电镜测量方法
Issue date: 2026-01-28 Implementation date: 2027-02-01
Issued by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
the Standardization Administration of the People's Republic of China
Contents
Foreword
Introduction
1 Scope
2 Normative References
3 Terms and Definitions
4 Summary of Method
5 Apparatus, Equipment, and Materials
6 Test Specimen
7 Test Method
8 Uncertainty Evaluation
9 Test Report
Annex A (Informative) Electroplating Method for Nickel Protective Layer
Bibliography
Microbeam Analysis — Method for Measuring Thickness of Gold Coatings Using Scanning Electron Microscopy
1 Scope
This document describes a method for measuring the thickness of gold coatings on various gold articles using scanning electron microscopy.
This document is applicable for the determination of gold coating thickness in the range of 25 nm to 50 μm. The measurement of gold coatings of other thicknesses may refer to this document.
NOTE: The minimum measurable thickness achievable is influenced by equipment performance parameters such as the image resolution and magnification of the scanning electron microscope, as well as factors including specimen preparation technique and electrical conductivity.
2 Normative References
The following documents contain provisions which, through normative reference in this text, constitute essential provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition (including any amendments) applies.
GB/T 27418 Evaluation and Expression of Uncertainty in Measurement
GB/T 27788 Microbeam Analysis — Guidelines for Calibration of Magnification of Scanning Electron Microscopy Images
3 Terms and Definitions
For the purposes of this document, the following terms and definitions apply.
3.1
average thickness
The arithmetic mean of a specified number of local thickness values measured at different positions within the basic measuring area.
3.2
scale marker
A line segment or interval on an image representing a specific actual length on the specimen.
[SOURCE: GB/T 27788-2020, 3.4]
3.3
secondary electron image
An electron beam scanning image formed by detecting secondary electrons with an energy less than 50 eV using a secondary electron detector. The secondary electron detector is insensitive to backscattered electrons.
[SOURCE: GB/T 21636-2021, 5.4.11]
3.4
backscattered electron image
An electron beam scanning image detected using a dedicated backscattered electron detector (e.g., scintillator, solid-state diode, channel plate, or negatively biased Everhart-Thornley detector).
[SOURCE: GB/T 21636-2021, 5.4.2]
3.5
intensity profile
The distribution of signal intensity along a selected line on an image.
[SOURCE: GB/T 43087-2023, 3.1.8]
3.6
differential processing
Calculating the difference between adjacent pixel data points within an intensity distribution map.
[SOURCE: GB/T 43087-2023, 3.1.2]
3.7
first-order difference curve
A curve plotted from the data sequence obtained after applying differential processing to the original data sequence.
4 Summary of Method
The main steps of the method described in this document are as follows:
a)Prepare a cross-section specimen of the gold coating and substrate using metallographic specimen preparation methods or focused ion beam (FIB) methods;
b) Calibrate the image scale marker of the scanning electron microscope using a reference material, in accordance with the provisions of GB/T 27788;
c) Observe the cross-section specimen of the gold coating and substrate using a scanning electron microscope. Acquire images that clearly show the interface between the protective layer (if applied), the gold coating, and the substrate, using secondary electron or backscattered electron imaging modes;
d) Obtain intensity profiles including the protective layer (if present), gold coating, and substrate, along with their interfaces, using software on the acquired image. Generate the corresponding first-order difference curve to determine the interface positions between the gold coating and the substrate, and between the gold coating and the protective layer (if present). Calculate the local thickness of the gold coating based on the distance between these two interfaces.
5 Apparatus, Equipment, and Materials
The required apparatus, equipment, and materials are as follows:
a)Scanning Electron Microscope (SEM): Equipped with an X-ray energy dispersive spectrometer, with a secondary electron image resolution better than 3 nm and a backscattered electron image resolution better than 10 nm;
b) Metallurgical Microscope;
c) Focused Ion Beam (FIB) System: For preparing specimens using the FIB method;
d) Ultrasonic Cleaner;
e) Micrometer-scale Certified Reference Material (CRM) or Reference Material (RM), with a minimum scale division nominal value less than 2 μm, used for calibrating the SEM image scale marker;
f) Equipment and materials required for preparing cross-section specimens: Equipment, reagents, and materials necessary for cutting, mounting, grinding, and polishing specimens;
g) Electroplating equipment and reagents: For electroplating a protective layer onto the specimen.
6 Test Specimen
6.1 Basic Requirements for the Specimen
The basic requirements for the specimen are as follows:
a) The observation surface of the specimen shall be perpendicular to the interface between the gold coating and the substrate to be measured. After preparation, the observation surface shall be flat, dry, free from contaminants, and free from scratches that could affect observation.
NOTE: Polished specimens are typically not etched, as etching may create corrosion grooves that introduce measurement errors.
b) It is recommended to prepare a conductive protective layer on the outer surface of the specimen's gold coating, or use a mounting method that preserves the edge, to avoid or mitigate edge effects during SEM observation.
c) The specimen shall have good electrical conductivity to reduce charging effects during SEM observation.
6.2 Conventional Preparation Method for the Specimen
6.2.1 Preparation of a Metallic Protective Layer
It is recommended to electroplate a metallic protective layer on the surface of the gold coating, with hardness similar to that of the coating. Electroplating with nickel is recommended, with a coating thickness not less than 1 μm. The electrolytic conditions and operating methods for nickel plating are detailed in Annex A. Alternatively, specimens can be directly mounted using a conductive mounting material with good edge retention properties to protect the edge.
NOTE: Specimens without a conductive protective layer on the outer gold coating are prone to edge effects during SEM observation, which can increase the uncertainty of the coating thickness measurement.
6.2.2 Sectioning of the Cross-Section Specimen
Cut a cross-section specimen of appropriate size perpendicular to the surface of the sample's coating.
NOTE: When the deviation of the observation surface from perpendicularity to the gold coating reaches 10°, the resulting measurement error is approximately 1.5%.
6.2.3 Mounting, Grinding, and Polishing of the Cross-Section Specimen
Methods for mounting, grinding, and polishing the cross-section specimen are detailed in GB/T 13298-2015, including the following aspects:
Standard
GB/T 17722-2026 Microbeam analysis—Method for thickness measurement on goldcoating layer by SEM (English Version)
Standard No.
GB/T 17722-2026
Status
to be valid
Language
English
File Format
PDF
Word Count
8500 words
Price(USD)
255.0
Implemented on
2026-8-1
Delivery
via email in 1~3 business day
Detail of GB/T 17722-2026
Standard No.
GB/T 17722-2026
English Name
Microbeam analysis—Method for thickness measurement on goldcoating layer by SEM
GB/T 17722-2026 Microbeam analysis—Method for thickness measurement on goldcoating layer by SEM English, Anglais, Englisch, Inglés, えいご
This is a draft translation for reference among interesting stakeholders. The finalized translation (passing through draft translation, self-check, revision and verification) will be delivered upon being ordered.
ICS 13.220.10
CCS H 57
National Standard of the People's Republic of China
GB/T 17722-2026
Replaces GB/T 17722-1999
Microbeam analysis - Method for thickness measurement on goldcoating layer by SEM
微束分析 金覆盖层厚度的扫描电镜测量方法
Issue date: 2026-01-28 Implementation date: 2027-02-01
Issued by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
the Standardization Administration of the People's Republic of China
Contents
Foreword
Introduction
1 Scope
2 Normative References
3 Terms and Definitions
4 Summary of Method
5 Apparatus, Equipment, and Materials
6 Test Specimen
7 Test Method
8 Uncertainty Evaluation
9 Test Report
Annex A (Informative) Electroplating Method for Nickel Protective Layer
Bibliography
Microbeam Analysis — Method for Measuring Thickness of Gold Coatings Using Scanning Electron Microscopy
1 Scope
This document describes a method for measuring the thickness of gold coatings on various gold articles using scanning electron microscopy.
This document is applicable for the determination of gold coating thickness in the range of 25 nm to 50 μm. The measurement of gold coatings of other thicknesses may refer to this document.
NOTE: The minimum measurable thickness achievable is influenced by equipment performance parameters such as the image resolution and magnification of the scanning electron microscope, as well as factors including specimen preparation technique and electrical conductivity.
2 Normative References
The following documents contain provisions which, through normative reference in this text, constitute essential provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition (including any amendments) applies.
GB/T 27418 Evaluation and Expression of Uncertainty in Measurement
GB/T 27788 Microbeam Analysis — Guidelines for Calibration of Magnification of Scanning Electron Microscopy Images
3 Terms and Definitions
For the purposes of this document, the following terms and definitions apply.
3.1
average thickness
The arithmetic mean of a specified number of local thickness values measured at different positions within the basic measuring area.
3.2
scale marker
A line segment or interval on an image representing a specific actual length on the specimen.
[SOURCE: GB/T 27788-2020, 3.4]
3.3
secondary electron image
An electron beam scanning image formed by detecting secondary electrons with an energy less than 50 eV using a secondary electron detector. The secondary electron detector is insensitive to backscattered electrons.
[SOURCE: GB/T 21636-2021, 5.4.11]
3.4
backscattered electron image
An electron beam scanning image detected using a dedicated backscattered electron detector (e.g., scintillator, solid-state diode, channel plate, or negatively biased Everhart-Thornley detector).
[SOURCE: GB/T 21636-2021, 5.4.2]
3.5
intensity profile
The distribution of signal intensity along a selected line on an image.
[SOURCE: GB/T 43087-2023, 3.1.8]
3.6
differential processing
Calculating the difference between adjacent pixel data points within an intensity distribution map.
[SOURCE: GB/T 43087-2023, 3.1.2]
3.7
first-order difference curve
A curve plotted from the data sequence obtained after applying differential processing to the original data sequence.
4 Summary of Method
The main steps of the method described in this document are as follows:
a)Prepare a cross-section specimen of the gold coating and substrate using metallographic specimen preparation methods or focused ion beam (FIB) methods;
b) Calibrate the image scale marker of the scanning electron microscope using a reference material, in accordance with the provisions of GB/T 27788;
c) Observe the cross-section specimen of the gold coating and substrate using a scanning electron microscope. Acquire images that clearly show the interface between the protective layer (if applied), the gold coating, and the substrate, using secondary electron or backscattered electron imaging modes;
d) Obtain intensity profiles including the protective layer (if present), gold coating, and substrate, along with their interfaces, using software on the acquired image. Generate the corresponding first-order difference curve to determine the interface positions between the gold coating and the substrate, and between the gold coating and the protective layer (if present). Calculate the local thickness of the gold coating based on the distance between these two interfaces.
5 Apparatus, Equipment, and Materials
The required apparatus, equipment, and materials are as follows:
a)Scanning Electron Microscope (SEM): Equipped with an X-ray energy dispersive spectrometer, with a secondary electron image resolution better than 3 nm and a backscattered electron image resolution better than 10 nm;
b) Metallurgical Microscope;
c) Focused Ion Beam (FIB) System: For preparing specimens using the FIB method;
d) Ultrasonic Cleaner;
e) Micrometer-scale Certified Reference Material (CRM) or Reference Material (RM), with a minimum scale division nominal value less than 2 μm, used for calibrating the SEM image scale marker;
f) Equipment and materials required for preparing cross-section specimens: Equipment, reagents, and materials necessary for cutting, mounting, grinding, and polishing specimens;
g) Electroplating equipment and reagents: For electroplating a protective layer onto the specimen.
6 Test Specimen
6.1 Basic Requirements for the Specimen
The basic requirements for the specimen are as follows:
a) The observation surface of the specimen shall be perpendicular to the interface between the gold coating and the substrate to be measured. After preparation, the observation surface shall be flat, dry, free from contaminants, and free from scratches that could affect observation.
NOTE: Polished specimens are typically not etched, as etching may create corrosion grooves that introduce measurement errors.
b) It is recommended to prepare a conductive protective layer on the outer surface of the specimen's gold coating, or use a mounting method that preserves the edge, to avoid or mitigate edge effects during SEM observation.
c) The specimen shall have good electrical conductivity to reduce charging effects during SEM observation.
6.2 Conventional Preparation Method for the Specimen
6.2.1 Preparation of a Metallic Protective Layer
It is recommended to electroplate a metallic protective layer on the surface of the gold coating, with hardness similar to that of the coating. Electroplating with nickel is recommended, with a coating thickness not less than 1 μm. The electrolytic conditions and operating methods for nickel plating are detailed in Annex A. Alternatively, specimens can be directly mounted using a conductive mounting material with good edge retention properties to protect the edge.
NOTE: Specimens without a conductive protective layer on the outer gold coating are prone to edge effects during SEM observation, which can increase the uncertainty of the coating thickness measurement.
6.2.2 Sectioning of the Cross-Section Specimen
Cut a cross-section specimen of appropriate size perpendicular to the surface of the sample's coating.
NOTE: When the deviation of the observation surface from perpendicularity to the gold coating reaches 10°, the resulting measurement error is approximately 1.5%.
6.2.3 Mounting, Grinding, and Polishing of the Cross-Section Specimen
Methods for mounting, grinding, and polishing the cross-section specimen are detailed in GB/T 13298-2015, including the following aspects:
