1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationSemiconductor devices Micro-electromechanical devicesPart 14: Forming limit measuring method of metallic film materialsBS EN 62047-14:2012National forewordThis British Standard i
2、s the UK implementation of EN 62047-14:2012. It is identical to IEC 62047-14:2012.The UK participation in its preparation was entrusted to Technical Committee EPL/47, Semiconductors.A list of organizations represented on this committee can be obtained on request to its secretary.This publication doe
3、s not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2012Published by BSI Standards Limited 2012 ISBN 978 0 580 72297 4 ICS 31.080.99 Compliance with a British Standard cannot confer immunity from le
4、gal obligations.This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 May 2012.Amendments issued since publicationAmd. No. Date Text affectedBRITISH STANDARDBS EN 62047-14:2012EUROPEAN STANDARD EN 62047-14 NORME EUROPENNE EUROPISCHE NORM April 2
5、012 CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Management Centre: Avenue Marnix 17, B - 1000 Brussels 2012 CENELEC - All rights of exploitation in any form and by any means reserved
6、worldwide for CENELEC members. Ref. No. EN 62047-14:2012 E ICS 31.080.99 English version Semiconductor devices - Micro-electromechanical devices - Part 14: Forming limit measuring method of metallic film materials (IEC 62047-14:2012) Dispositifs semiconducteurs - Dispositifs microlectromcaniques - P
7、artie 14: Mthode de mesure des limites de formage des matriaux couche mtallique (CEI 62047-14:2012) Halbleiterbauelemente - Bauelemente der Mikrosystemtechnik - Teil 14: Verfahren zur Ermittlung der Grenzformnderung metallischer Dnnschichtwerkstoffe (IEC 62047-14:2012) This European Standard was app
8、roved by CENELEC on 2012-04-03. CENELEC members are bound to 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 nat
9、ional standards may be obtained on application to the CEN-CENELEC 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
10、own language and notified to the CEN-CENELEC Management Centre 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, France, Germany, Greece, Hungary, I
11、celand, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. BS EN 62047-14:2012EN 62047-14:2012 - 2 - Foreword The text of document 47F/108/FDIS, future edition 1 of I
12、EC 62047-14, prepared by SC 47F, “Micro-electromechanical systems“, of IEC TC 47, “Semiconductor devices“ was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as EN 62047-14:2012. The following dates are fixed: latest date by which the document has to be implemented at national lev
13、el by publication of an identical national standard or by endorsement (dop) 2013-01-03 latest date by which the national standards conflicting with the document have to be withdrawn (dow) 2015-04-03 Attention is drawn to the possibility that some of the elements of this document may be the subject o
14、f 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 62047-14:2012 was approved by CENELEC as a European Standard without any modification. BS EN 62047-14:2012- 3 - EN 62047-14:2
15、012 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 edition cited
16、 applies. For undated references, the latest edition of the referenced document (including any amendments) applies. NOTE When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD applies. Publication Year Title EN/HD Year IEC 62047-1 2005 Sem
17、iconductor devices - Micro-electromechanical devices - Part 1: Terms and definitions EN 62047-1 2006 BS EN 62047-14:2012 2 62047-14 IEC:2012 CONTENTS 1 Scope . 5 2 Normative references . 5 3 Terms, definitions and symbols 5 3.1 Terms and definitions 5 3.2 Symbols 6 4 Testing method . 6 4.1 General .
18、 6 4.2 Equipment . 6 4.3 Specimen 7 5 Test procedure and analysis . 8 5.1 Test procedure 8 5.2 Data analysis 9 6 Test report 10 Annex A (informative) Principles of the forming limit diagram . 11 Annex B (informative) Grid marking method . 13 Annex C (informative) Gripping method . 15 Annex D (inform
19、ative) Strain measuring method 17 Figure 1 Equipment and tools for forming limit tests . 7 Figure 2 Rectangular specimens with six kinds of aspect ratio . 8 Figure 3 Strain for forming limit measurement 9 Figure 4 Construct the forming limit diagram by plotting the major and minor strains 9 Figure A
20、.1 Forming limit diagram . 11 Figure A.2 Hemispherical punch for forming limit measurement . 11 Figure A.3 Grid for forming limit measurement . 12 Figure A.4 Loading path of the specimen with various aspect ratios . 12 Figure B.1 Procedure of a photographic grid marking method 13 Figure B.2 Procedur
21、e for an inkjet grid marking method . 14 Figure C.1 Gripping of the specimen using a ring shaped die . 15 Figure C.2 Gripping of the specimen using adhesive bonding 16 Figure D.1 Set up for strain measurement using digital camera 17 Figure D.2 Example of pixel converting image of deformed specimen 1
22、7 Table 1 List of letter symbols . 6 BS EN 62047-14:201262047-14 IEC:2012 5 SEMICONDUCTOR DEVICES MICRO-ELECTROMECHANICAL DEVICES Part 14: Forming limit measuring method of metallic film materials 1 Scope This part of IEC 62047 describes definitions and procedures for measuring the forming limit of
23、metallic film materials with a thickness range from 0,5 m to 300 m. The metallic film materials described herein are typically used in electric components, MEMS and micro-devices. When metallic film materials used in MEMS (see 2.1.2 of IEC 62047-1:2005) are fabricated by a forming process such as im
24、printing, it is necessary to predict the material failure in order to increase the reliability of the components. Through this prediction, the effectiveness of manufacturing MEMS components by a forming process can also be improved, because the period of developing a product can be reduced and manuf
25、acturing costs can thus be decreased. This standard presents one of the prediction methods for material failure in imprinting process. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated
26、 references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 62047-1:2005, Semiconductor devices Micro-electromechanical devices Part 1: Terms and definitions 3 Terms, definitions and symbols 3.1 Terms and
27、definitions For the purposes of this document, the terms and definitions given in IEC 62047-1 and the following apply. 3.1.1 circular grid grid used for measuring the localized deformation of the specimens within the circle 3.1.2 grid patterns pattern marked on the surface of the testing material pe
28、rmitting immediate and direct measurement of the formability for the metallic film materials Note 1 to entry The grid consists of a pattern of small circles or rectangles. 3.1.3 major axis longest line of the deformed elliptical shape, which passes through both focuses of the ellipse BS EN 62047-14:
29、2012 6 62047-14 IEC:2012 3.1.4 minor axis longest line of the deformed elliptical shape, which is perpendicular to the major axis 3.1.5 square grid grid used for measuring the overall deformation of the testing material 3.2 Symbols For the purpose of this document, letter symbols given in Table 1 ar
30、e used. Table 1 List of letter symbols Name and designation Letter symbol Grid size initial diameter of the grid before deformation diameter of the grid along the major axis after deformation diameter of the grid along the minor axis after deformation d0d1d2Strain major strain minor strain 12Equipme
31、nt, tool and specimen size diameter of the hemispherical punch inner diameter of the die hole diameter of the bead ring fillet radius of the upper die edge thickness of the testing specimen height of the testing specimen width of the testing specimen Dpunch Ddie Dbead rdet h w 4 Testing method 4.1 G
32、eneral The forming limit diagram (FLD) is determined by pressing the micro film material using a hemispherical punch. This pressing process is performed until the film material fractures. The major and minor strains of a deformed specimen can be measured in many ways, for example, by using a digital
33、 camera module or an optical device. However, using a digital camera module with sufficient resolution and a high magnifying power lens is recommended. NOTE See Annex A for principles of forming limit diagram. 4.2 Equipment Micro press equipment is utilized as the loading equipment for FLD tests as
34、described in Figure 1. A hemispherical punch is attached to the micro press to stretch the film material to measure the forming limits of the specimen. Conventional hard chrome coating to the punch surface using hexavalent chromium is recommended to guarantee a surface roughness less than 0,8 m (RMS
35、: Root Mean Square). In addition, lubricants such as graphite can be applied for reducing the friction force between the surfaces of the punch and the specimen. The movement of the punch is controlled by a constant crosshead speed of the measuring devices in the micro press. The punch speed shall be
36、 lowered to the quasi-static condition. A punch speed of less than 20 m/s is recommended in order not to result in the dynamic inertia BS EN 62047-14:201262047-14 IEC:2012 7 effect during the test. Although the dimension of the hemispherical punch and the test samples can be varied with forming prod
37、uct and inspected measuring region, it is recommended that the dimension should be determined as the following ratio. Ddie= Dpunch+ 2,5t (1) Dbead= 2 Dpunch(2) It is also recommended that the hemispherical punch diameter and the die edge radius should be 5 mm and 0,5 mm respectively. DpunchDdierdeDb
38、ead3123124Key 1 upper die 2 lower die 3 specimen 4 hemispherical punch Figure 1 Equipment and tools for forming limit tests 4.3 Specimen Rectangular specimens with different aspect ratios shall be used in the test. At least six kinds of specimens with the aspect ratios of 1,0, 1,5, 1,75, 2,0, 3,5 an
39、d 7,0 are recommended as shown in Figure 2 in order to cover the various loading paths on the domain of the forming limit diagram. h = 2,5 Dpunch(3) beaddierdeDun1 IEC 200/12 BS EN 62047-14:2012 8 62047-14 IEC:2012 Figure 2 Rectangular specimens with six kinds of aspect ratio Grids shall be marked t
40、o the surface of the testing sample to measure the localized and overall deformation of the film material. The grid consists of a pattern of small circles or rectangles. It is recommended to arrange the grid patterns with an interval range from 50 m to 200 m and that the thickness of the grid is les
41、s than 10 % of the specimen thickness. NOTE See Figure A.3 for detailed grid pattern. 5 Test procedure and analysis 5.1 Test procedure In a FLD test, the following items from a) to e) are steps to obtain a localized fracture of a specimen which is firstly observed. Then the values of a major strain
42、and a minor strain which are used to quantify the deformation of the specimen will be measured. a) Preparation of the specimen Specimens with different aspect ratios are prepared to conduct the test. NOTE 1 Both the positive and negative region of the FLD curve can be obtained by varying the aspect
43、ratio of the specimen and the lubricant. b) Grid marking on the specimen Appropriate marking conditions which have a lesser effect on the microstructure and the properties of materials should be applied in the grid marking since the thickness of the film is relatively smaller. NOTE 2 See Annex B for
44、 detail expression of several grid marking methods. c) Gripping the specimen In order to measure the strain only in the testing region, it is important that the sample should be clamped without any sliding. Also, pre-fracture should not occur when it is being clamped. NOTE 3 See Annex C for several
45、recommended gripping methods. d) Moving the punch until the specimen fails The hemispherical punch moves by controlling the constant crosshead speed of equipment until the localized fracture of the specimen is first observed. e) Measuring the major and minor strains of deformed specimen Major and mi
46、nor strains of the deformed specimen are measured representatively using the digital camera module with a high magnifying power lens. The recommended magnification factor of the camera lens is less than 5 m/pixel in order to measure the strain precisely. NOTE 4 See Annex D for strain measuring metho
47、d. f) Construct the FLD by plotting the measured major and minor strains (refer to Figure 4). Aspect ratio = Specimen height (h) Specimen width (w) 1 1,5 1,75 2 3,5 7 h w IEC 201/12 BS EN 62047-14:201262047-14 IEC:2012 9 5.2 Data analysis In order to quantify the deformation of the specimen, two kin
48、ds of strains major and minor strains are measured between the initial state of the circle and the deformed elliptical shape. After the circular grid deforms, the longest dimensions of the ellipse is major axis and the dimension perpendicular to the major axis is the minor axis, as explained in Figu
49、re 3. Figure 3 Strain for forming limit measurement The major strain, 1, and the minor strain, 2, are calculated with following equations: 011lndd=(4)022lndd=(5)Here, d0is the initial diameter of the circular grid while d1and d2represent the major and the minor diameters of the grid after deformation. 0Minor strain %Major strain %-10-20-30-40 4030201010203040506070802112333322223Key 1 fracture 2 good 3 failure