1、_SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirely voluntary, and its applicability and suitability for any particular use, including any patent infringement arising theref
2、rom, is the sole responsibility of the user.”SAE reviews each technical report at least every five years at which time it may be revised, reaffirmed, stabilized, or cancelled. SAE invites your written comments and suggestions.Copyright 2016 SAE InternationalAll rights reserved. No part of this publi
3、cation may be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE.TO PLACE A DOCUMENT ORDER: Tel: 877-606-7323 (inside USA and Canada)Tel: +1 724-776-4970 (out
4、side USA)Fax: 724-776-0790Email: CustomerServicesae.orgSAE WEB ADDRESS: http:/www.sae.orgSAE values your input. To provide feedback on thisTechnical Report, please visithttp:/standards.sae.org/AS6171/3AEROSPACESTANDARDAS6171/3Issued 2016-10Techniques for Suspect/Counterfeit EEE Parts Detection by X-
5、ray Fluorescence Test MethodsRATIONALESince counterfeit electrical, electronic, and electromechanical (EEE) components are likely to have some level of material difference from the genuine components, techniques that identify the chemical elements in different areas of a part are essential to benchm
6、arking authentic parts (exemplars) and comparing them to parts under consideration. X-ray fluorescence (XRF) is one such technique that can be applied both to the external surfaces and internal elements of a part. The method itself is nondestructive by nature.INTRODUCTIONBecause many methods of coun
7、terfeiting of EEE components involve change of material from the original part, X-ray fluorescence (XRF) spectroscopy can provide a method of inspection of parts and detecting differences in their material composition. The method has been used extensively to detect nonconforming parts in electronics
8、 and in many other product areas. The implementation of RoHS1 requirements of the European Union and similar laws in other countries, resulted in wide spread use of XRF testing to confirm that electronic part leads do or do not contain lead (Pb). This document provides an introduction to the theory
9、and practice for application to counterfeit electronic part detection.TABLE OF CONTENTS1. SCOPE 31.1 Purpose. 32. REFERENCES 32.1 Applicable Documents 32.1.1 SAE Publications. 32.2 Related Publications . 32.3 Terms and Definitions . 42.4 Acronyms and Abbreviations 43. DESCRIPTION OF METHODOLOGY/PROC
10、EDURE 43.1 Material Control/ESD Handling . 63.2 Additional Considerations . 64. TEST EQUIPMENT AND CALIBRATION. 64.1 Equipment . 64.1.1 Benchtop XRF. 64.1.2 Hand-Held XRF. 71 Restrictions on Hazardous SubstancesSAE INTERNATIONAL AS6171/3 Page 2 of 224.2 Analysis Software 74.3 Selection Summary of Ty
11、pe of XRF Tool 74.4 Controls and Calibration 85. REQUIREMENTS . 85.1 Sampling . 85.2 Categories of Testing/Risk Levels 85.3 Comparison of Test Results for Determination of Suspect/Counterfeit 95.4 Counterfeit Detection Test Procedure. 95.4.1 Generic Steps in Performing a Bulk Material Analysis with
12、any XRF Instrument. 105.4.2 Plating Thickness Measurement. 115.4.3 When to Perform Plating Thickness Measurement 125.4.4 Steps in Performing Analysis on a Small Sample with a Hand-held System . 145.4.5 Generic Steps in Performing Analysis on a Large Sample, with No X-ray Blocking Present, with a Han
13、d-held System 155.5 Test Plan . 155.6 Analysis and Interpretation of Results 155.7 Test Report . 175.8 Training and Certification 185.8.1 Personnel Qualification and Certification 185.8.2 Laboratory/Test Facility. 205.8.3 Proficiency. 215.9 Data Retention Requirements. 226. NOTES 226.1 Revision Indi
14、cator 22FIGURE 1 XRF PRINCIPLE OF OPERATION. 4FIGURE 2 SCHEMATIC OF AN XRF SYSTEM. 5FIGURE 3 UNUSABLE XRF SPECTRAL INFORMATION 10FIGURE 4 XRF SPECTRUM WITH ELEMENT PEAKS 11FIGURE 5 CIRCULAR CONNECTOR WITH CONTACTS 14FIGURE 6 HAND-HELD POSITIONED TO ANALYZE CONTACTS . 14TABLE 1 RECOMMENDED XRF TESTS
15、8TABLE 2 EXAMPLE INDICATIONS OF SUSPECT COUNTERFEIT COMPONENTS (SEE NOTE 1 REGARDING CONFORMANCE REQUIREMENTS) 17SAE INTERNATIONAL AS6171/3 Page 3 of 221. SCOPEXRF technique for counterfeit detection is applicable to electrical, electronic and electromechanical (EEE) parts as listed in AS6171 Genera
16、l Requirements. In general, the detection technique is meant for use on piece parts prior to assembly on a circuit board or on the parts that are removed from a circuit board. The applicability spans a large swath of active, passiveand electromechanical parts.If AS6171/3 is invoked in the contract,
17、the base document, AS6171 General Requirements shall also apply.1.1 PurposeThe purpose of this document is to provide information and instructions on how to use XRF as a technique to verify the materials and finishes of EEE parts to compare with the original design, construction and material require
18、ments. The process of detection is based on identification of elements (or absence thereof) in a component. The indication of counterfeitrisk can also be based on the presence of and concentration levels of materials under consideration. The counterfeit detection process using XRF can be applied to
19、components as received or on delidded, decapsulated, or otherwise prepared parts. For reliable decision making, findings from XRF analysis need to be compared with material composition information of appropriate exemplars, compared with each other in the lot, or compared with the original manufactur
20、ers documented specifications.2. REFERENCES2.1 Applicable DocumentsThe following publications form a part of this document to the extent specified herein. The latest issue of SAE publications shall apply. The applicable issue of other publications shall be the issue in effect on the date of the purc
21、hase order. In theevent of conflict between the text of this document and references cited herein, the text of this document takes precedence. Nothing in this document, however, supersedes applicable laws and regulations unless a specific exemption has been obtained.2.1.1 SAE PublicationsAvailable f
22、rom SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or +1 724-776-4970 (outside USA), www.sae.org.1 AS5553, Fraudulent/Counterfeit Electronic Parts; Avoidance, Detection, Mitigation, and Disposition.2 AS6171, Test Method Standard, Gener
23、al Requirements, Suspect/Counterfeit, Electrical, Electronic, and Electromechanical Parts.2.2 Related PublicationsThe following publications are provided for information purposes only and are not a required part of this SAE Aerospace Technical Report.1 JEDEC, JESD 213, Standard Test Method Utilizing
24、 X-ray Fluorescence (XRF) for Analyzing Component Finishes and Solder Alloys to Determine Tin (Sn) - Lead (Pb) Content.2 Naval Air Systems Command, “Solder Alloy Analysis: X-ray Fluorescence Test Equipment Evaluation Report,” NAVAIRin conjunction with Crane Division, Naval Surface Warfare Center, De
25、fense Logistics Agency, July 2009.3 Beckhoff, B.; Kanngieer, B.; Langhoff, N.; Wedell, R.; Wolff, H. (Eds.), Handbook of Practical X-ray Fluorescence Analysis, Springer 2006.4 NAS 410, Certification and Qualification of Non-Destructive Test Personnel, AIA. 5 ISO, ISO 17025, General Requirements for
26、the Competence of Testing and Calibration Laboratories.SAE INTERNATIONAL AS6171/3 Page 4 of 226 MIL-STD-1580B, Destructive Physical Analysis for Electronic, Electromagnetic, and Electromechanical Parts.7 MIL-PRF-38535, Integrated Circuits (Microcircuits) Manufacturing, General Specification for (w/A
27、mendment 1) Revision: J, Dated: 14 May 2012. 8 ASTM B568-98 (2009), Standard Test Method for Measurement of Coating Thickness by X-ray Spectrometry.9 ISO 3497:2000, Metallic coatings - Measurement of coating thickness - X-ray spectrometric methods.2.3 Terms and DefinitionsSee 2.2 of AS6171 General R
28、equirements.2.4 Acronyms and AbbreviationsSee 2.3 of AS6171 General Requirements.3. DESCRIPTION OF METHODOLOGY/PROCEDUREX-ray Fluorescence (XRF) is a fast and simple method to detect material composition. Its most notable qualities include no, or minimal, sample preparation, nondestructive analysis,
29、 and compatibility with solid, liquid, and powdered samples. XRF spectrometers range from light hand-held devices to table-top machines, and floor mounted instruments employing liquid nitrogen. The principle of operation is detecting the energy level of ejected electrons under incident X-ray. Fluore
30、scence refers to a phenomenon where absorption of radiation of one type of energy results in emission of radiation of a different energy. Figure 1 shows the basic principle and Figure 2 shows a schematic of an XRF system. In the diagram, K, L, and M denote the three innermost shells and KD and KE ar
31、e the energy emissions that result from electrons transitioning between shells L and K and between shells M and K respectively.Figure 1 - XRF principle of operationSAE INTERNATIONAL AS6171/3 Page 5 of 22X-ray tube (1) (cathode, anode) which provides the primary beam (2)Primary beam filter (optional)
32、 (3)Collimator (4)Sample (5)Characteristic fluorescence radiation (6)Detector (7)Count rate (8)Spectrum (9)Measurement ResultsFigure 2 - Schematic of an XRF systemPrinciple of X-ray FluorescenceIncident electromagnetic waves (X-rays) of sufficient energy excite electrons in an atoms inner orbital (c
33、ore electrons). The excited electrons are ejected from the inner orbital. Electrons from an outer orbital then move to the inner orbital to fill the vacancies. During this transition, the electron emits an X-ray photon whose energy is equal to the difference between the two energy levels involved in
34、 the transition.Principle of operation of an XRF spectrometer:a. Incident X-ray beam strikes sampleb. Excitation of characteristic lines (X-ray fluorescence)c. Element specific characteristic radiation is detected and a spectrum is createdd. Software evaluates spectrum for presence/absence of elemen
35、tsSAE INTERNATIONAL AS6171/3 Page 6 of 223.1 Material Control/ESD HandlingMaterial control and ESD handling shall conform to 3.9.5 of AS6171 General Requirements.3.2 Additional ConsiderationsThis section outlines the cautions to be taken and limitations of the XRF counterfeit risk detection techniqu
36、e. This section also discusses the needs for additional techniques for confirming or invalidating the results of XRF techniques. Some of technical limitations for the XRF technique are also discussed.XRF assumes a homogeneous matrix in order to quantify the presence of any given element in the sampl
37、e. In heterogeneous samples such as electronic components, XRF yields relative qualitative results on the presence of elements. When the zone of analysis on the electronic component is locally homogeneous and the XRF beam size and focus is on that homogeneous area, the results can be accepted as bei
38、ng from a homogeneous matrix.Using a plating thickness or plating thickness/composition mode of XRF measurement can provide useful information and assist in the analysis of the component. Device construction information of base material, plated layers, and top finish layer can be analyzed/compared t
39、o OCM design, variation between devices, or to historical variations in materials such as changes in connector contact plating (Au/Ag/Cu versus Au/Cu versus Au/Ni/Cu) or solder finish (Sn versus Sn-Pb versusother lead free). Knowledge of the top layer thickness and its contribution to the spectrum w
40、ill provide useful insight during the analysis.There is potential for false positive and false negative detection of elements. For example, when using XRF in the plating thickness/composition mode, sample elements absent from the measurement application file and incorrectly identified layers in that
41、 file can cause erroneous detection. The analyst should review the raw instrument data in the form of an X-ray energy spectrum to verify the analyzers reading. The X-ray energy spectrum shows what elements should be present in the plating thickness/composition mode report with X-ray peaks present at
42、 known energies, and if these elements were not correctly detected in the report it can quickly be determined from the spectrum that the measurement application file needs revision (refer to Figures 3 and 4). While XRF is capable of detecting elements from Aluminum to Uranium, the calibration set on
43、 most instruments is generally limited to measuring somewhere between 20 to 25 elements at one time. With complex matrices there is the potential for false positives or negatives if the instrument is not calibrated for all the elements that occur in the sample. Analysis of the raw data produced by t
44、he instrument, in the form of an X-ray energy spectrum, may be consulted to verify the instruments reading. Additionally, reference techniques such as Induction-Coupled Plasma (ICP) or SEM-EDS can be used to validateXRF results.24. TEST EQUIPMENT AND CALIBRATION4.1 Equipment This section specifies m
45、inimum XRF equipment specifications for suspect part identification. The type of XRF equipment chosen for the evaluation is influenced by several factors including the component location to be tested, whether or not the component to be tested is loose or installed onto a circuit board assembly, and
46、the size or surface area of the component lead or termination area.4.1.1 Benchtop XRFThe overall power of the system is important to ensure that the appropriate depth of the material is scanned and enough energy is available to reach the proper levels of shells. In order to assure proper function, p
47、eriodic hardware checks should be performed on the instrument per the manufacturers specifications. It is also recommended that the standard operating procedures include frequently analyzing known reference materials to verify the instruments accuracy.2 All of the analytical instruments mentioned (I
48、CP; SEM-EDS) are subject to recording false positive or negative results. Proper training by the manufacturers of analytical instrumentation including XRF is required to minimize this problem.SAE INTERNATIONAL AS6171/3 Page 7 of 22The system needs to be based on an X-ray tube with an accelerating vo
49、ltage set at minimum of 40keV. Either a proportional counter or a semiconductor detector can be present in these units. To facilitate examination of parts of different sizes, multiple collimators are necessary. (A collimator needs to be selected that is smaller than the area that needs to be measured.) Using Benchtop XRF equipment is the preferred method for counterfeit parts detection, as outlined in the Sel
