1、BSI Standards PublicationSemiconductor devices Micro-electromechanical devicesPart 22: Electromechanical tensile test method for conductive thin films on flexible substratesBS EN 62047-22:2014National forewordThis British Standard is the UK implementation of EN 62047-22:2014. It isidentical to IEC 6
2、2047-22:2014.The UK participation in its preparation was entrusted to TechnicalCommittee EPL/47, Semiconductors.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all the necessary provisions ofa contract. Use
3、rs are responsible for its correct application. The British Standards Institution 2014.Published by BSI Standards Limited 2014ISBN 978 0 580 77555 0ICS 01.080.99Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of
4、theStandards Policy and Strategy Committee on 31 October 2014.Amendments/corrigenda issued since publicationDate Text affectedBRITISH STANDARDBS EN 62047-22:2014EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 62047-22 September 2014 ICS 01.080.99 English Version Semiconductor devices - Micro-elect
5、romechanical devices - Part 22: Electromechanical tensile test method for conductivethin films on flexible substrates (IEC 62047-22:2014) Dispositifs semiconducteurs - Dispositifsmicrolectromcaniques - Partie 22: Mthode dessai de traction lectromcaniquepour les couches minces conductrices sur des su
6、bstrats souples (CEI 62047-22:2014) Halbleiterbauelemente - Bauelemente derMikrosystemtechnik - Teil 22: Elektromechanisches Zug-Prfverfahren frleitfhige Dnnschichten auf flexiblen Substraten(IEC 62047-22:2014) This European Standard was approved by CENELEC on 2014-07-24. CENELEC members are bound t
7、o comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-C
8、ENELEC Management Centre or to any CENELEC member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Cen
9、tre has the same status as the official versions.CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Ital
10、y, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland,Turkey and the United Kingdom. European Committee for Electrotechnical Standardization Comit Europen de Normalisation ElectrotechniqueEuropisches Komitee fr Ele
11、ktrotechnische Normung CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2014 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members. Ref. No. EN 62047-22:2014 E EN 62047-22:2014 - 2 - Foreword The text of document 47F/186/FDIS, future e
12、dition 1 of IEC 62047-22, prepared by SC 47F “Microelectromechanical systems” of IEC/TC 47 “Semiconductor devices“ was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as EN 62047-22:2014. The following dates are fixed: latest date by which the document has to be implemented at nat
13、ional level by publication of an identical national standard or by endorsement (dop) 2015-04-24 latest date by which the national standards conflicting with the document have to be withdrawn (dow) 2017-07-24 Attention is drawn to the possibility that some of the elements of this document may be the
14、subject of patent rights. CENELEC and/or CEN shall not be held responsible for identifying any or all such patent rights. Endorsement notice The text of the International Standard IEC 62047-22:2014 was approved by CENELEC as a European Standard without any modification. BS EN 62047-22:2014- 3 - EN 6
15、2047-22:2014 Annex ZA (normative) Normative references to international publications with their corresponding European publications The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edit
16、ion cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. NOTE 1 When an International Publication has been modified by common modifications, indicated by (mod), the relevant EN/HD applies. NOTE 2 Up-to-date information on the latest
17、 versions of the European Standards listed in this annex is available here: www.cenelec.eu Publication Year Title EN/HD Year IEC 62047-2 2006 Semiconductor devices - Micro-electromechanical devices - Part 2: Tensile testing method of thin film materials EN 62047-2 2006 IEC 62047-3 2006 Semiconductor
18、 devices - Micro-electromechanical devices - Part 3: Thin film standard test piece for tensile testing EN 62047-3 2006 IEC 62047-8 2011 Semiconductor devices - Micro-electromechanical devices - Part 8: Strip bending test method for tensile property measurement of thin films EN 62047-8 2011 ISO 527-3
19、 1995 Plastics - Determination of tensile properties - Part-3: Test conditions for films and sheets EN ISO 527-3 1995 BS EN 62047-22:2014 2 IEC 62047-22:2014 IEC 2014 CONTENTS 1 Scope 5 2 Normative references 5 3 Terms, definitions, symbols and designations 5 3.1 Terms and definitions 5 3.2 Symbols
20、and designations 6 4 Test piece . 6 4.1 General . 6 4.2 Shape of a test piece 6 4.3 Measurement of dimensions . 7 5 Testing method and test apparatus 7 5.1 Test principle 7 5.2 Test machine 7 5.3 Test procedure 9 5.4 Test environment 9 6 Test report . 9 Figure 1 Bilayered test piece 6 Figure 2 Schem
21、atic of an electromechanical test machine . 8 Figure 3 Electromechanical tensile grip 9 Table 1 Symbols and designations of a test piece 6 BS EN 62047-22:2014IEC 62047-22:2014 IEC 2014 5 SEMICONDUCTOR DEVICES MICRO-ELECTROMECHANICAL DEVICES Part 22: Electromechanical tensile test method for conducti
22、ve thin films on flexible substrates 1 Scope This part of IEC 62047 specifies a tensile test method to measure electromechanical properties of conductive thin micro-electromechanical systems (MEMS) materials bonded on non-conductive flexible substrates. Conductive thin-film structures on flexible su
23、bstrates are extensively utilized in MEMS, consumer products, and flexible electronics. The electrical behaviours of films on flexible substrates differ from those of freestanding films and substrates due to their interfacial interactions. Different combinations of flexible substrates and thin films
24、 often lead to various influences on the test results depending on the test conditions and the interfacial adhesion. The desired thickness of a thin MEMS material is 50 times thinner than that of the flexible substrate, whereas all other dimensions are similar to each other. 2 Normative references T
25、he 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 amendments) applies. IEC 6204
26、7-2:2006, Semiconductor devices Micro-electromechanical devices Part 2: Tensile testing method of thin film materials IEC 62047-3:2006, Semiconductor devices Micro-electromechanical devices Part 3: Thin film standard test piece for tensile testing IEC 62047-8:2011, Semiconductor devices Micro-electr
27、omechanical devices Part 8: Strip bending test method for tensile property measurement of thin films ISO 527-3:1995, Plastics Determination of tensile properties Part 3: Test conditions for films and sheets 3 Terms, definitions, symbols and designations 3.1 Terms and definitions For the purposes of
28、this document, the following terms and definitions apply. 3.1.1 gauge factor GFratio of the change in electrical resistance divided by the original resistance (Ro, resistance in the undeformed configuration) to engineering strain (e) Note 1 to entry: Gauge factor is expressed as GF= (R RO)/ROe, wher
29、e R is the electrical resistance in the deformed configuration. BS EN 62047-22:2014 6 IEC 62047-22:2014 IEC 2014 3.1.2 elongation at electrical failure Atelicengineering strain value at which the electrical resistance starts to exceed a predefined limit 3.2 Symbols and designations The shape of the
30、test piece and symbols are presented in Figure 1 and Table 1, respectively. The overall shape of the test piece is similar to a conventional thin-film or sheet test piece (in accordance with ISO 527-3) for tensile tests, but it has a multilayered structure. Figure 1 Bilayered test piece Table 1 Symb
31、ols and designations of a test piece Symbol Unit Designation l1m Gauge length for strain and resistance change measurements l2m Overall length h1m Thickness of the first layer (or thin film) h2m Thickness of the second layer (or substrate) b m Width 4 Test piece 4.1 General The test piece shall be p
32、repared using the same fabrication process as the actual device fabricated for flexible MEMS. Machining of the test piece shall be performed carefully to prevent formation of cracks or flaws and delamination in the test piece. Chemical etching or mechanical machining with a very sharp tool shall be
33、applied to shape the test piece. 4.2 Shape of a test piece The shape of a test piece is shown in Figure 1. Because the change in electrical resistance is related to strain or stress, electrical resistance shall be measured in a region of nearly uniform strain. To measure electrical resistance, attac
34、h lead wires to the conductive thin film of the test piece. Conductive thin films deposited on flexible substrates are usually very thin compared with the diameter of the lead wires, and the lead wires are easily detached from the test piece during the electromechanical test. Therefore, place the le
35、ad wires in tensile grips and secure the electrical contact by applying mechanical contact force. Tensile grips are described in detail in 5.2. For uniform strain distribution, the shape of the test piece is a rectangular strip, not a dog bone (see Figure 1 of ISO 527-3:1995 for other rectangular te
36、st pieces). To eliminate the effect of the fixed boundary near the grips (l1), the gauge length shall be at least 20 times larger than the width (b). IEC 1841/14 l1l2b h2h1BS EN 62047-22:2014IEC 62047-22:2014 IEC 2014 7 4.3 Measurement of dimensions To analyze the test results, the test piece dimens
37、ions shall be accurately measured because the dimensions are used to determine the mechanical properties of test materials. Gauge length (l1), width (b), and thickness (h1, h2) should be measured with an error of less than 5 %. Thickness measurement shall be performed according to Annex C of IEC 620
38、47-2:2006 and to Clause 6 of IEC 62047-3:2006. There can be some combinations of thin film and substrate where it is difficult to fulfil the tolerance of thickness measurement. In this case the average and the standard deviation of the thickness measurement should be reported. 5 Testing method and t
39、est apparatus 5.1 Test principle The test is performed by applying a tensile load to a test piece. The tensile strain induced by the tensile load shall be uniform in a pre-defined gauge section in the elastic region of the substrate or the thin MEMS material. To measure the change in electrical resi
40、stance along with the change in mechanical strain, carefully select the gauge section. The gauge section for measuring mechanical strain shall be coincident with or scalable to that for measuring electrical resistance. This constraint is an important point in this standard. 5.2 Test machine The test
41、 machine is similar to a conventional tensile test machine except that it is capable of measuring electrical resistance during the test. The electrical measurement circuit can be a 2-wire or 4-wire method depending on the magnitude of the electrical resistance of the test piece. For a test piece wit
42、h an electrical resistance greater than 1 k, a 2-wire method can be utilized for ease of measurement. For a test piece with an electrical resistance less than 1 k, the 4-wire method (Kelvin method) shall be utilized to eliminate contact and lead wire resistance. A schematic of the test machine is sh
43、own in Figure 2a). For a material sensitive to stress concentration and local plastic deformation, a test piece with rounded, gripped ends shall be used according to Figure 1 of IEC 62047-2:2006, and the test machine in Figure 2b) should be used. BS EN 62047-22:2014 8 IEC 62047-22:2014 IEC 2014 a) T
44、est machine setup using grips with an electrical contact b) Test machine setup using electrical contacts on the test piece Key 1 Machine frame 2 Grip 3 Loadcell 4 Actuator 5 Volt meter 6 Specimen Figure 2 Schematic of an electromechanical test machine To measure electrical resistance, a tensile grip
45、 with electrical contacts is utilized, and the number of electrical contacts is dependent on the electrical measurement method (2-wire or 4-wire method). A schematic of the tensile grip is shown in Figure 3. In this standard, strain is estimated from the grip-to-grip distance. An optical or mechanic
46、al extensometer shall be used to measure the grip-to-grip distance. IEC 1843/14 IEC 1842/14 BS EN 62047-22:2014IEC 62047-22:2014 IEC 2014 9 a) Photograph of the installed tensile grip b) Schematic of the tensile grip Key 1 Probe pin 2 Bolt 3 Insulating jig 4 Specimen Figure 3 Electromechanical tensi
47、le grip 5.3 Test procedure The test procedure is as follows: a) Fix the test piece using the test apparatus tensile grip. The longitudinal direction of the test piece shall be aligned with the actuating direction of the test apparatus, and the deviation angle shall be less than 1 degree, as specifie
48、d in 4.4 of IEC 62047-8:2011. b) Verify the electrical measurement unit as well as the loadcell and strain measurement unit. The three signals provided by the measurement units shall be measured simultaneously with no time delay. c) Apply a tensile load to the test piece at a constant strain rate (o
49、r grip-to-grip displacement rate). The strain rate shall range from 0,01 min1to 10 min1depending on the material system of the test piece and the actual usage condition of the customer. d) Unload the test apparatus when electrical failure occurs in the test piece. After testing, carefully remove the test piece from the test apparatus to analyze its failure mechanism. If possible, preserve the fractured test piece after testing. 5.4 Test environment Because electric