1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS ISO 11505:2012Surface chemical analysis General procedures forquantitative compositionaldepth profiling by glowdischarge optical emissionspectrometryBS ISO 11505:2012 BRITISH
2、STANDARDNational forewordThis British Standard is the UK implementation of ISO 11505:2012. The UK participation in its preparation was entrusted to TechnicalCommittee CII/60, Surface chemical analysis.A list of organizations represented on this committee can be obtained on request to its secretary.T
3、his publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2013. Published by BSI Standards Limited 2013ISBN 978 0 580 77085 2 ICS 71.040.40 Compliance with a British Standard cannot con
4、fer immunity from legal obligations.This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 January 2013.Amendments issued since publicationDate T e x t a f f e c t e dBS ISO 11505:2012 ISO 2012Surface chemical analysis General procedures for quan
5、titative compositional depth profiling by glow discharge optical emission spectrometryAnalyse chimique des surfaces Modes opratoires gnraux pour le profilage en profondeur compositionnel quantitatif par spectromtrie dmission optique dcharge luminescenteINTERNATIONAL STANDARDISO11505First edition2012
6、-12-15Reference numberISO 11505:2012(E)BS ISO 11505:2012ISO 11505:2012(E)ii ISO 2012 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2012All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanica
7、l, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISOs 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.orgPublis
8、hed in SwitzerlandBS ISO 11505:2012ISO 11505:2012(E) ISO 2012 All rights reserved iiiContents PageForeword iv1 Scope . 12 Normative references 13 Principle 14 Apparatus . 14.1 Glow discharge optical emission spectrometer 15 Adjusting the glow discharge spectrometer system settings . 35.1 General . 3
9、5.2 Setting the discharge parameters of a DC source . 45.3 Setting the discharge parameters of an RF source .65.4 Minimum performance requirements 76 Sampling 97 Calibration 97.1 General . 97.2 Calibration specimens 97.3 Validation specimens 117.4 Determination of the sputtering rate of calibration
10、and validation specimens .117.5 Emission intensity measurements of calibration specimens 127.6 Calculation of calibration equations 127.7 Validation of the calibration . 127.8 Verification and drift correction . 138 Analysis of test specimens .148.1 Adjusting discharge parameters . 148.2 Setting of
11、measuring time and data acquisition rate 148.3 Quantifying depth profiles of test specimens 149 Expression of results .159.1 Expression of quantitative depth profile . 159.2 Determination of total coating mass per unit area .159.3 Determination of average mass fractions .1610 Precision 1611 Test rep
12、ort 16Annex A (normative) Calculation of calibration constants and quantitative evaluation of depth profiles 17Annex B (informative) Suggested spectral lines for determination of given elements 31Bibliography .33BS ISO 11505:2012ISO 11505:2012(E)ForewordISO (the International Organization for Standa
13、rdization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right t
14、o 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 International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.International Stan
15、dards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an Inte
16、rnational Standard requires approval by at least 75 % of the member bodies casting a vote.Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights.ISO 11505 wa
17、s prepared by Technical Committee ISO/TC 201, Surface chemical analysis, Subcommittee SC 8, Glow discharge spectroscopy.iv ISO 2012 All rights reservedBS ISO 11505:2012INTERNATIONAL STANDARD ISO 11505:2012(E)Surface chemical analysis General procedures for quantitative compositional depth profiling
18、by glow discharge optical emission spectrometry1 ScopeThis International Standard describes a glow discharge optical emission spectrometric (GD-OES) method for the determination of the thickness, mass per unit area and chemical composition of surface layer films.It is limited to a description of gen
19、eral procedures of quantification of GD-OES and is not applicable directly for the quantification of individual materials having various thicknesses and elements to be determined. NOTE Any individual standard for a test material will have to specify a scope of a thickness of the surface layer as wel
20、l as analyte elements, and include results of interlaboratory tests for validation of the methods.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 ap
21、plies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 14707, Surface chemical analysis Glow discharge optical emission spectrometry (GD-OES) Introduction to useISO 14284, Steel and iron Sampling and preparation of samples for the determin
22、ation of chemical composition3 PrincipleThe analytical method described here involves the following processes:a) cathodic sputtering of the surface layer in a direct current or radio frequency glow discharge device;b) excitation of the analyte atoms and ions in the plasma formed in the glow discharg
23、e device;c) spectrometric measurement of the intensities of characteristic spectral emission lines of the analyte atoms and ions as a function of sputtering time (qualitative depth profile);d) conversion of the qualitative depth profile in units of intensity versus time to mass fraction versus depth
24、 by means of calibration functions (quantification). Calibration of the system is achieved by measurements on calibration specimens of known chemical composition and measured sputtering rate.4 Apparatus4.1 Glow discharge optical emission spectrometer4.1.1 GeneralThe required instrumentation includes
25、 an optical emission spectrometer system consisting of a Grimm type10or similar glow discharge source (direct current or radio frequency powered) and a simultaneous optical spectrometer as described in ISO 14707, capable of providing suitable spectral ISO 2012 All rights reserved 1BS ISO 11505:2012I
26、SO 11505:2012(E)lines for the analyte elements. Sequential optical spectrometers (monochromators) are not suitable, since several analytical wavelengths must be measured simultaneously at high data acquisition speed.The inner diameter of the hollow anode of the glow discharge source should be in the
27、 range 1 mm to 8 mm. A cooling device for thin specimens, such as a metal block with circulating cooling liquid, is also recommended, but not strictly necessary for implementation of the method.Since the principle of determination is based on continuous sputtering of the surface layer, the spectrome
28、ter shall be equipped with a digital readout system for time-resolved measurement of the emission intensities. A system capable of a data acquisition speed of at least 500 measurements/second per spectral channel is recommended, but, for a large number of applications, speeds of 50 measurements/seco
29、nd per spectral channel are acceptable.4.1.2 Selection of spectral linesFor each analyte to be determined, there exist a number of spectral lines which can be used. Suitable lines shall be selected on the basis of several factors, including the spectral range of the spectrometer used, the analyte ma
30、ss fraction range, the sensitivity of the spectral lines and any spectral interference from other elements present in the test specimens. For applications where several of the analytes of interest are major elements in the specimens, special attention shall be paid to the occurrence of self-absorpti
31、on of certain highly sensitive spectral lines (so-called resonance lines). Self-absorption causes nonlinear calibration curves at high analyte mass fraction levels, and strongly self-absorbed lines should therefore be avoided for the determination of major elements. Suggestions concerning suitable s
32、pectral lines are given in Annex B. Spectral lines other than those listed may be used, as long as they have favourable characteristics.4.1.3 Selection of glow discharge source type4.1.3.1 Anode sizeMost GD-OES instruments on the market are delivered with options to use various anode diameters, with
33、 2 mm, 4 mm and 8 mm being the most common. Some older instruments have one anode only, usually 8 mm, while the most commonly used anode in modern instruments is 4 mm. A larger anode requires larger specimens and higher power during analysis; therefore the specimen is heated to a greater extent. On
34、the other hand, a larger anode gives rise to a plasma of larger volume that emits more light, resulting in lower detection limits (i.e. higher analytical sensitivity). Furthermore, a larger anode helps to mask inhomogeneity within a surface layer. This may or may not be an advantage, depending on th
35、e application. In a large number of applications, the 4 mm anode is a good compromise. However, in surface analysis applications it is rather common to encounter problems of overheating of the specimens due to, e.g. surface layers of poor heat conductivity and/or very thin specimens. In such cases,
36、the smaller 2 mm anode is preferable, even if there is some loss of analytical sensitivity.4.1.3.2 Type of power supplyThe glow discharge source can be either a type powered by a direct current (DC) power supply or a radio frequency (RF) type. The most important difference is that the RF type can sp
37、utter both conductive and non-conductive specimens; hence this is the only type that can be used for, e.g. polymer coatings and insulating oxide layers. On the other hand, it is technically simpler to measure and control the electrical source parameters (voltage, current, power) of a DC type. Severa
38、l commercially available GD-OES systems can be delivered with the option to switch between DC and RF operation, but RF-only systems also exist. In short, there are a very large number of applications where DC or RF sources can be used and several where only an RF source can be used.2 ISO 2012 All ri
39、ghts reservedBS ISO 11505:2012ISO 11505:2012(E)4.1.3.3 Mode of operationBoth DC and RF sources can be operated in several different modes with respect to the control of the electrical parameters (current, voltage, power) and the pressure. There are several reasons for this: “historical” reasons (old
40、er instruments have simpler but functional power supplies, while the technology has evolved so that newer models have more precise and easier-to-operate source control); different manufacturers have chosen different solutions for source control; there are some application-related issues where a part
41、icular mode of operation is to be preferred.This International Standard gives instructions for optimizing the source parameters based on several available modes of operation. The most important reason for this is to make these instructions comprehensive so as to include several types of instrument.
42、In most applications, there is no major difference between these modes in terms of analytical performance, but there are other differences in terms of practicality and ease of operation. For instance, a system equipped with active pressure regulation will automatically be adjusted to the same electr
43、ical source parameters every time a particular analytical method is used. Without this technology, some manual adjustment of the pressure to achieve the desired electrical source parameters is normally required.NOTE It should be noted in this context that what is known as the emission yield1112forms
44、 the basis for calibration and quantification as described in this International Standard. The emission yield has been found to vary with the current, the voltage and, to a lesser extent, the pressure17. It is impossible in practice to maintain all three parameters constant for all test specimens, d
45、ue to variations in the electrical characteristics of different materials. In several instrument types, the electrical source parameters (the plasma impedance) can therefore be maintained constant by means of automatic systems that vary the pressure during analysis. Alternatively, there exist method
46、s to correct for impedance variations by means of empirically derived functions17, and this type of correction is implemented in the software of commercially available GD-OES systems.5 Adjusting the glow discharge spectrometer system settings5.1 GeneralFollow the manufacturers instructions or locall
47、y documented procedures for preparing the instrument for use.RF sources differ from DC sources in the respect that for several instrument models, only the applied (forward) RF power can be measured, not the actual power developed in the glow discharge plasma. The applied RF power is normally in the
48、range 10100 W, but it must be noted that the RF power losses in connectors, cables, etc. vary considerably between different instrument models. Typical power losses are in the range 1050 % of the applied power. Furthermore, the possibilities to measure the additional electrical parameters voltage an
49、d current in the plasma are more or less restricted due to technical difficulties with RF systems, and several existing instrument models can only measure the applied RF power.There is no difference between DC and RF concerning the possibilities to measure the pressure. However, there are large pressures differentials in a Grimm type source, and pressure readings obtained depend on the location of the pressure gauge. Some instrument models have a pressure gauge attached to measure the actual pressure in the plasma, while others h
