1、BSI Standards PublicationBS ISO 14707:2015Surface chemical analysis Glow discharge opticalemission spectrometry (GD-OES) Introduction touseBS ISO 14707:2015 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 14707:2015. It supersedes BS ISO 14707:2000 which is wit
2、hdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee CII/60, Surface chemical analysis.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract
3、. Users are responsible for its correctapplication. The British Standards Institution 2015.Published by BSI Standards Limited 2015ISBN 978 0 580 83086 0ICS 71.040.40Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority
4、 of theStandards Policy and Strategy Committee on 31 March 2015.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e dBS ISO 14707:2015 ISO 2015Surface chemical analysis Glow discharge optical emission spectrometry (GD-OES) Introduction to useAnalyse chimique des surfaces Spectro
5、mtrie dmission optique dcharge luminescente Introduction son emploiINTERNATIONAL STANDARDISO14707Second edition2015-03-15Reference numberISO 14707:2015(E)BS ISO 14707:2015ISO 14707:2015(E)ii ISO 2015 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2015All rights reserved. Unless otherwise specif
6、ied, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISO
7、s member body in the country of the requester.ISO copyright officeCase postale 56 CH-1211 Geneva 20Tel. + 41 22 749 01 11Fax + 41 22 749 09 47E-mail copyrightiso.orgWeb www.iso.orgPublished in SwitzerlandBS ISO 14707:2015ISO 14707:2015(E)Foreword ivIntroduction v1 Scope 12 Normative references 13 Te
8、rms and definitions . 14 Principle 25 Apparatus . 25.1 Glow discharge optical emission source . 25.2 Optical unit . 55.3 Photoelectric detectors and measuring devices 56 Procedure. 66.1 Verification tests of apparatus . 66.1.1 General 66.1.2 Glow discharge source 76.1.3 Optical unit and electric mea
9、suring device . 76.2 Determination . 76.2.1 General 76.2.2 Preparation of the required calibration specimens . 76.2.3 Setting up of measuring conditions and analysis of specimens 86.2.4 Quality check of results 86.2.5 Test report . 8Annex A (informative) Safety .10Bibliography .12 ISO 2015 All right
10、s reserved iiiContents PageBS ISO 14707:2015ISO 14707:2015(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical commit
11、tees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the In
12、ternational Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the d
13、ifferent types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO s
14、hall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents).Any trade name used in this document
15、 is information given for the convenience of users and does not constitute an endorsement.For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TB
16、T) see the following URL: Foreword - Supplementary informationThe committee responsible for this document is ISO/TC 201, Surface chemical analysis, Subcommittee SC 8, Glow discharge spectroscopy.This second edition cancels and replaces the first edition (ISO 14707:2000), which has been technically r
17、evised.Annex A of this International Standard is for information only.iv ISO 2015 All rights reservedBS ISO 14707:2015ISO 14707:2015(E)IntroductionGlow discharge optical emission spectrometry (GD-OES) is used to determine the elemental composition of solid samples. GD-OES can be used for either bulk
18、 or depth profile analysis. In bulk analysis, changes in elemental composition with depth into the specimen are assumed to be negligible. In contrast, the main goal of depth profile analysis is usually to gain information concerning such changes of composition. Layer thicknesses amenable to GD-OES d
19、epth profiling range from a few nanometres to approximately one hundred micrometres. An average of the concentration within the crater will be obtained and therefore the lateral resolution of GD-OES corresponds to the inner diameter of the anode.As is true for any instrumental analysis method, the q
20、uality of a GD-OES analysis depends markedly on the correct optimization and operation of the instrumentation. This International Standard provides guidelines of practice that are to be followed to ensure that GD-OES analyses are of the highest possible quality. ISO 2015 All rights reserved vBS ISO
21、14707:2015BS ISO 14707:2015Surface chemical analysis Glow discharge optical emission spectrometry (GD-OES) Introduction to use1 ScopeThis International Standard provides guidelines that are applicable to bulk and depth profiling GD-OES analyses. The guidelines discussed herein are limited to the ana
22、lysis of rigid solids, and do not cover the analysis of powders, gases or solutions. Combined with specific standard methods which are available now and in the future, these guidelines should enable the regulation of instruments and the control of measuring conditions.Although several types of glow
23、discharge optical emission sources have been developed over the years, the Grimm type with a hollow anode accounts for a very large majority of glow discharge optical emission devices currently in use both for dc and rf sources. It should be noted, however, that the cathode contact is often located
24、at the back of the sample, in e.g. the Marcus type source, rather than at the front as in the original Grimm design. It should be clearly understood that the guidelines contained herein are equally applicable to both and other source designs and that the Grimm type source is used only as an example.
25、2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendm
26、ents) applies.ISO 3497:1990, Metallic coatings Measurement of coating thickness X-ray spectrometric methodsISO 5725-1:1994, Accuracy (trueness and precision) of measurement methods and results Part 1: General principles and definitionsISO 5725-2:1994, Accuracy (trueness and precision) of measurement
27、 methods and results Part 2: Basic method for the determination of repeatability and reproducibility of a standard measurement methodISO 5725-3:1994, Accuracy (trueness and precision) of measurement methods and results Part 3: Intermediate measures of the precision of a standard measurement methodIS
28、O 5725-4:1994, Accuracy (trueness and precision) of measurement methods and results Part 4: Basic methods for the determination of the trueness of a standard measurement methodISO 6955:1982, Analytical spectroscopic methods Flame emission, atomic absorption, and atomic fluorescence VocabularyISO 115
29、05, Surface chemical analysis General procedures for quantitative compositional depth profiling by glow discharge optical emission spectrometry3 Terms and definitionsFor the purposes of this document, the terms and definitions given in ISO 3497, ISO 5725-1, ISO 5725-2, ISO 5725-3, ISO 5725-4, and IS
30、O 6955 apply.INTERNATIONAL STANDARD ISO 14707:2015(E) ISO 2015 All rights reserved 1BS ISO 14707:2015ISO 14707:2015(E)4 PrincipleAnalysis by GD-OES involves the following operations:a) preparation of the sample to be analysed, generally in the form of a flat plate or disc of dimensions appropriate t
31、o the instrument or analytical requirement (round or rectangular samples with a width of more than 3 mm, generally 20 mm to 100 mm, are suitable);b) atomization and excitation of the analytes to be determined by means of ion sputtering and inter-particle collisions occurring in the glow discharge pl
32、asma;c) measurement of the emission intensities of characteristic spectral lines of the analytes (for depth profiling, emission intensities are recorded as a function of time);d) determination of the analyte concentrations contained in the sample by calibration with reference materials of known comp
33、osition (for depth profiling, the sputtered depth as a function of time is also determined by calibration with reference materials of known composition and sputtering rates).A diagram of a typical GD-OES system is presented in Figure 1. GD-OES is based on the use of a glow discharge device as an opt
34、ical emission source. The glow discharge device consists of a vacuum chamber filled with a supporting gas, usually argon. The glowing plasma, from which the discharge takes its name, is maintained by a controlled high voltage of 200 V to 2 000 V applied between the anode and cathode in the plasma ga
35、s. The solid sample to be analysed serves as the cathode.Atomization of sample material in the glow discharge is the result of cathode sputtering, the destruction of the negative electrode (cathode) in a gas discharge due to the impact of fast charged and neutral particles. Ions formed in the plasma
36、 are accelerated toward the cathode surface by the electric field in the plasma. When an ion or neutral atom collides with the surface, its kinetic energy may be transferred to atoms on the surface, causing some of these surface atoms to be ejected into the plasma. Once in the plasma, these sputtere
37、d sample atoms may be ionized and excited through inelastic collisions with electrons or other species. The majority of these excited analyte atoms and ions then emit characteristic optical emission upon relaxing into the lower electronic state. The optical emission is analysed by an optical spectro
38、meter containing a dispersive element, normally a diffraction grating. The intensities of element-specific spectral lines are translated to electrical signals by means of appropriate detectors. A polychromator is commonly employed, so that many elements can be quantified simultaneously. Spectral lin
39、es that are not contained in the line set of the polychromator can be accessed by means of a scanning monochromator, if one is available. Also CCD instruments exist, where a spectrum over a wide spectral range can be measured continuously. In practice almost all elements in the periodic table can be
40、 determined, including metals, metalloids and non-metals.5 ApparatusAt a minimum, the apparatus consists of the following:5.1 Glow discharge optical emission sourceA diagram of a Grimm type glow discharge optical emission device is shown in Figure 2. Several modifications in the device have been int
41、roduced by instrument manufacturers. As noted in Clause 4, the sample effectively serves as the cathode. The anode takes the form of a tube with an inner diameter of 1 mm to 10 mm, typically 4 mm. The distance between the front face of the anode and the surface of the cathode is usually between 0,1
42、mm and 0,3 mm. As a result, ion sputtering is confined to a circular region of the sample surface with a diameter approximately equal to the inner diameter of the anode.The glow discharge device requires several peripheral pieces of equipment for its operation. These include an electric power supply
43、, one or two vacuum pumps, a source of plasma gas, a means of delivering that gas into the device in a controlled manner and a vacuum gauge. A cooling device, such as a metal block with circulating cooling liquid, is sometimes necessary for thin samples.a) Source parameters2 ISO 2015 All rights rese
44、rvedBS ISO 14707:2015ISO 14707:2015(E)Glow discharge devices may be operated in either direct current (dc) or radio-frequency (rf) mode. Combinations of these two modes, such as the use of an rf voltage superposed onto a dc voltage, have also been reported. In both the dc and rf power modes, a pulse
45、d discharge is also employed for switching the applied power periodically.1) For dc operation, the pertinent electrical parameters are discharge current (1 mA to 200 mA) and voltage (200 V to 2 000 V). In addition to the electrical parameters, other parameters are important for the characteristics o
46、f the device. These include the inner diameter of the anode (1 mm to 10 mm), gas type and purity (for example, argon, 99,999 %), gas flow rate or gas pressure introduced (100 ml/min to 500 ml/min, 100 Pa to 1 500 Pa, see note below) and physical characteristics of the sample material (for example, s
47、econdary electron emission yield and sputtering yield). The combined effects of all of these factors determine the spectrochemical character of the glow discharge plasma. Generally, it is recommended that the gas flow rate or the gas pressure be varied in real time, in order to achieve constant volt
48、age and cur- rent. As an example, typical operating conditions for dc GD-OES bulk analysis of low-alloy steels are 250 ml/min argon flow rate, 600 V to 1 000 V discharge voltage and 20 mA to 60 mA discharge current, for an anode of 4 mm inner diameter. The sputtering rate in this case is typically 1
49、00 nm/s varying from 20 nm/s to 160 nm/s for the conditions given in the example. ISO 2015 All rights reserved 3BS ISO 14707:2015ISO 14707:2015(E)Key1 spectrometer 8 rowland circle 15 sample2 electrical lead-in 9 cooling system 16 personal computer system3 preamplifier 10 gas control system 17 grating4 light intensity measuring circuit 11 RF power supply 18 entrance slit5 vacuum/gas flush control system 12 DC power supply 19 lens6 photomultiplier 13 control circuit 20 glow discharge source7 exit slit 14 local computer 21
