ANSI STM11.31-2012 Evaluating the Performance of Electrostatic Discharge Shielding Materials C Bags.pdf

1、ANSI/ESD STM11.31-2012 Reaffirmation of ANSI/ESD STM11.31-2006 For Evaluating the Performance of Electrostatic Discharge Shielding Materials Bags Electrostatic Discharge Association 7900 Turin Road, Bldg. 3 Rome, NY 13440 An American National Standard Approved July 25, 2012 ANSI/ESD STM11.31-2012 ES

2、D Association Standard Test Method for Evaluating the Performance of Electrostatic Discharge Shielding Materials Bags Approved February 12, 2012 ESD Association ANSI/ESD STM11.31-2012 Electrostatic Discharge Association (ESDA) standards and publications are designed to serve the public interest by e

3、liminating misunderstandings between manufacturers and purchasers, facilitating the interchangeability and improvement of products, and assisting the purchaser in selecting and obtaining the proper product for his particular needs. The existence of such standards and publications shall not in any re

4、spect preclude any member or non-member of the Association from manufacturing or selling products not conforming to such standards and publications. Nor shall the fact that a standard or publication that is published by the Association preclude its voluntary use by non-members of the Association, wh

5、ether the document is to be used either domestically or internationally. Recommended standards and publications are adopted by the ESDA in accordance with the ANSI Patent policy. Interpretation of ESDA Standards: The interpretation of standards in-so-far as it may relate to a specific product or man

6、ufacturer is a proper matter for the individual company concerned and cannot be undertaken by any person acting for the ESDA. The ESDA Standards Chairman may make comments limited to an explanation or clarification of the technical language or provisions in a standard, but not related to its applica

7、tion to specific products and manufacturers. No other person is authorized to comment on behalf of the ESDA on any ESDA Standard. THE CONTENTS OF ESDAS STANDARDS AND PUBLICATIONS ARE PROVIDED “AS-IS,” AND ESDA MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESSED OR IMPLIED, OF ANY KIND, WITH RESPECT TO

8、 SUCH CONTENTS. ESDA DISCLAIMS ALL REPRESENTATIONS AND WARRANTIES, INCLUDING WITHOUT LIMITATION, WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR USE, TITLE, AND NON-INFRINGEMENT. ESDA STANDARDS AND PUBLICATIONS ARE CONSIDERED TECHNICALLY SOUND AT THE TIME THEY ARE APPROVED FOR PUB

9、LICATION. THEY ARE NOT A SUBSTITUTE FOR A PRODUCT SELLERS OR USERS OWN JUDGEMENT WITH RESPECT TO ANY PARTICULAR PRODUCT DISCUSSED, AND ESDA DOES NOT UNDERTAKE TO GUARANTEE THE PERFORMANCE OF ANY INDIVIDUAL MANUFACTURERS PRODUCTS BY VIRTUE OF SUCH STANDARDS OR PUBLICATIONS. THUS, ESDA EXPRESSLY DISLA

10、IMS ANY RESPONSIBILITY FOR DAMAGES ARISING FROM THE USE, APPLICATION, OR RELIANCE BY OTHERS ON THE INFORMATION CONTAINED IN THESE STANDARDS OR PUBLICATIONS. NEITHER ESDA, NOR ITS MEMBERS, OFFICERS, EMPLOYEES OR OTHER REPRESENTATIVES WILL BE LIABLE FOR DAMAGES ARISING OUT OF, OR IN CONNECTION WITH, T

11、HE USE OR MISUSE OF ESDA STANDARDS OR PUBLICATIONS, EVEN IF ADVISED OF THE POSSIBILITY THEREOF. THIS IS A COMPREHENSIVE LIMITATION OF LIABILITY THAT APPLIES TO ALL DAMAGES OF ANY KIND, INCLUDING, WITHOUT LIMITATION, LOSS OF DATA, INCOME OR PROFIT, LOSS OF OR DAMAGE TO PROPERTY, AND CLAIMS OF THIRD P

12、ARTIES. Published by: Electrostatic Discharge Association 7900 Turin Road, Bldg. 3 Rome, NY 13440 Copyright 2012 by ESD Association All rights reserved No part of this publication may be reproduced in any form, in an electronic retrieval system or otherwise, without the prior written permission of t

13、he publisher. Printed in the United States of America ISBN: 1-58537-209-9 CAUTION NOTICE DISCLAIMER OF WARRANTIES DISCLAIMER OF GUARANTY LIMITATION ON ESDAs LIABILITY ANSI/ESD STM11.31-2012 i (This foreword is not part of ESD Association Standard Test Method ANSI/ESD STM11.31-2012) FOREWORD It is th

14、e intent of this standard to provide industry with a common, repeatable method for testing and determining the shielding abilities of electrostatic shielding bags. This test method improved upon the existing industry test method for static shielding by controlling some of the variables that were not

15、 previously addressed such as: - discharge waveform characteristics - capacitive probe capacitance - bag size This test method also has made a significant change by discontinuing the use of two (2) voltage probes and incorporating a single current probe for measurement purposes. This was done to eli

16、minate the problems that were encountered with attempting to balance the voltage probes which resulted in measurement errors. This standard test method1 was originally approved on June 23, 1994 and was designated ESD S11.31-1994. ANSI/ESD STM11.31-2001 was a reaffirmation, re-designation of ESD S11.

17、31-1994 and approved on February 4, 2001. ANSI/ESD STM11.31-2006 was a reaffirmation of ANSI/ESD STM11.31-2001 and approved on September 10, 2006. ANSI/ESD STM11.31-2012 is a reaffirmation of ANSI/ESD STM11.31-2006 and was approved on February 12, 2012. Four editorial changes were made from the 2006

18、 version: removing definitions that are in the ESD Association glossary; adding a personnel safety section; updated referenced publications; and changed the term “environmental test chamber” to “controlled test environment”. At the time ANSI/ESD STM11.31-2012 was prepared, the 11.0 Packaging Subcomm

19、ittee had the following members: Brent Beamer, Chair 3M Kevin Duncan, TAS Rep Seagate Technology Kurt Edwards Lubrizol Gene Felder Desco Industries, Inc. Dale Parkin Seagate Technology Tim Prass Raytheon Jeff Salisbury Flextronics Jose Sancho NASA/Honeywell/TSI David E. Swenson Affinity Static Contr

20、ol Consulting, LLC Julius Turangan Ovation, Inc. Robert Vermillion RMV Technology Group, LLC Stanley Weitz Electro-Tech Systems, Inc. Craig Zander Prostat Corporation 1ESD Association Standard Test Method (STM): A definitive procedure for the identification, measurement and evaluation of one or more

21、 qualities, characteristics, or properties of a material, product, system, or process that yield a reproducible test results. ANSI/ESD STM11.31-2012 ii At the time the ESD S11.31-1994 version was prepared, the 11.0 Packaging Subcommittee had the following members: Ron Gibson, Chair Celestica, Inc. B

22、en Baumgartner Lockheed Missiles and Space Company Brent Beamer Static Control Components Rich Draskinas Web Technologies, Inc Mary Fouts Seco Industries Steve Fowler ESD Flooring Systems John T. Kinnear Jr., TAC IBM Steve Koehn 3M Bob Renninger AT&T Bell Labs Barry Shaiman Simco Company Inc. Stan W

23、eitz ETS The following individuals made significant contributions to ESD S11.31-1994: Steve Halperin Steve Halperin & Associates David E. Swenson 3M ANSI/ESD STM11.31-2012 iii TABLE OF CONTENTS 1.0 SCOPE AND PURPOSE 1 1.1 SCOPE . 1 1.2 PURPOSE 1 2.0 REFERENCED PUBLICATIONS 1 3.0 DEFINITIONS 1 4.0 PE

24、RSONNEL SAFETY . 1 5.0 REQUIRED EQUIPMENT . 1 5.1 ESD SIMULATOR 1 5.2 WAVEFORM VERIFICATION EQUIPMENT 2 5.2.1 Oscilloscope . 2 5.2.2 Current Probe. 2 5.2.3 High Voltage Resistor 2 5.3 CAPACITIVE PROBE . 2 5.4 DISCHARGE ELECTRODE AND GROUND ELECTRODE . 2 5.5 BAG SIZE 2 5.6 COMPUTER / SOFTWARE . 2 5.7

25、 CONTROLLED TEST ENVIRONMENT 2 6.0 ESD SIMULATOR WAVEFORM VERIFICATION PROCEDURE . 3 7.0 SYSTEM VERIFICATION PROCEDURE . 3 8.0 TEST PROCEDURE / CONDITIONING . 4 9.0 REPORTING . 4 ANNEXES Annex A (Informative): Energy Calculation Program . 7 FIGURES Figure 1: ESD Simulator . 5 Figure 2: Parallel Plat

26、e Capacitive Probe . 5 Figure 3: Current Waveform through a 500-ohm Resistor . 6 ESD Association Standard Test Method ANSI/ESD STM11.31-2012 1 ESD Association Standard Test Method for Evaluating the Performance of Electrostatic Discharge Shielding Materials Bags 1.0 SCOPE AND PURPOSE 1.1 Scope This

27、test method evaluates the performance of electrostatic discharge shielding bags. The design voltage for the test apparatus is 1000 volts. 1.2 Purpose The purpose of this standard is to ensure that testing labs, using this test method to evaluate a given packaging material, will obtain similar result

28、s. 2.0 REFERENCED PUBLICATIONS ANSI/ESDA/JEDEC JS-001, ESDA/JEDEC Joint Standard for Electrostatic Discharge Sensitivity Testing - Human Body Model (HBM) - Component Level2ASTM D 257, Standard Test Methods for DC Resistance or Conductance of Insulating Materials33.0 DEFINITIONS The terms used in the

29、 body of this document are in accordance with the definitions found in ESD ADV1.0, ESD Associations Glossary of Terms available for complimentary download at http:/www.esda.org/keydownloads.html. 4.0 PERSONNEL SAFETY The procedures and equipment described in this document may expose personnel to haz

30、ardous electrical conditions. Users of this document are responsible for selecting equipment that complies with applicable laws, regulatory codes, and both external and internal policy. Users are cautioned that this document cannot replace or supersede any requirements for personnel safety. Ground f

31、ault circuit interrupters (GFCI) and other safety protection should be considered wherever personnel might come into contact with electrical sources. Electrical hazard reduction practices should be exercised and proper grounding instructions for equipment should be followed. The resistance measureme

32、nts obtained through the use of this test method shall not be used to determine the relative safety of personnel exposed to high AC or DC voltages. 5.0 REQUIRED EQUIPMENT 5.1 ESD Simulator A basic ESD simulator is shown in Figure 1. This simulator and the resulting waveforms were taken from ANSI/ESD

33、A/JEDEC JS-001. The equivalent circuit for the simulator consists of a 100 pF capacitor in series with a 1,500 ohm resistor. 2ESD Association, 7900 Turin Road, Bldg. 3, Rome, NY 13440, 315-339-6937 3American Society for Testing and Materials (ASTM) 1916 Race Street, Philadelphia, PA 19103-1187, 215-

34、299-5400 ANSI/ESD STM11.31-2012 2 5.2 Waveform Verification Equipment Equipment capable of verifying the pulse waveforms defined in this standard shall include but is not limited to: a storage oscilloscope, a high voltage resistor and a suitable current probe. 5.2.1 Oscilloscope A digital storage os

35、cilloscope capable of a 200 MHz single shot bandwidth and a minimum sampling rate of 500 mega samples per second. 5.2.2 Current Probe The current probe shall have a minimum frequency response of 500 MHz. (Included in the current probes that meet this requirement are a Tektronix CT-1, CT-2 and CT-6.)

36、 The maximum cable length is 1 meter. 5.2.3 High Voltage Resistor The resistor shall be a 500 ohm, 1% tolerance, 1000 volt, low inductance, sputtered metal film (Caddock Industries type MG or equivalent). 5.3 Capacitive Probe A parallel plate capacitive probe shall be constructed per Figure 2. The c

37、apacitance for the probe shall be 8 pF 2 pF. The probe capacitance can be verified per Section 7.0 (C). The spacer between the plates shall be made of an insulating material such as polycarbonate or acrylic. 5.4 Discharge Electrode and Ground Electrode The discharge electrode and the ground electrod

38、e shall be 3.8 0.025 cm (1.5 0.010 inches) in diameter and shall be made of a conductive material. The support area that surrounds the ground electrode should be 20 x 25 cm (8 x 10 inches) and have a surface resistivity greater than 1 x 1013ohms per square as measured per ASTM D 257. 5.5 Bag Size Th

39、e bags used for this test should be 20 x 25 cm (8 x 10 inches), with 20 cm (8 inches) being the open end. NOTE: If other bag sizes are used, care must be taken to ensure that the same size bag is used to provide consistent and fair comparison of bags from various manufacturers. Bags, which are not l

40、arge enough to have the capacitive probe completely inside the bag may yield erroneous results. Bags with substantial differences in thickness may yield results that do not correlate due to the increased transmission length through the bag. 5.6 Computer / Software A computer should be used to analyz

41、e the data that is acquired by the oscilloscope. A generic description of the analysis system is described in Annex A. 5.7 Controlled Test Environment An environment that can meet the following conditions is required: Control humidity to 12% RH 3% RH at a temperature of 23 C 2 C (73 F 3 F) ANSI/ESD

42、STM11.31-2012 3 Control humidity to 50% RH 5% RH at a temperature of 23 C 2 C (73 F 3 F) 6.0 ESD SIMULATOR WAVEFORM VERIFICATION PROCEDURE The following procedure shall be used to verify the resistive current (Ip) waveform from the ESD simulator. A) Connect the 500 ohm resistor specified in Section

43、5.2.3 to the wiring from the ESD simulator discharge and ground connections keeping the cabling as short as possible (the cables used should be the same as those used to perform the shielding test). Connect the current probe around the wire end of the resistor which is connected to the ESD simulator

44、 ground. Connect the discharge electrode cable to the tester output and the ground electrode cable to equipment ground. NOTE: The conductive discharge and ground electrodes are not used for this portion of the test. B) Connect the current probe to the storage oscilloscope. Set the oscilloscope input

45、 resistance to 50 ohms. (Match the impedance of the probe and the oscilloscope input.) C) Set the ESD simulator discharge voltage to 1000 volts. D) Set the horizontal time scale in the oscilloscope to 5 ns per division and initiate a pulse. Observe the waveform rise time, peak current and leading ed

46、ge ringing. All parameters shall be within the limits specified in Figure 3(A) and Section 6.0 (E). E) If necessary adjust the ESD simulator voltage level until a peak current (IP) of 0.50 amperes 10% is obtained. This voltage level represents an equivalent 1000 volt discharge level. This is the vol

47、tage level that will be used in Section 8.0. F) Set the horizontal time scale in the oscilloscope to 100 ns per division and observe the complete current waveform. The pulse shall meet the decay time requirement (td) as shown in Figure 3(B). G) Using the computer analyze the resulting current wavefo

48、rm. The software must be capable of calculating energy for different resistances. For this portion of the procedure the resistance is 2000 ohms (this consists of the 1500 ohm ESD simulator resistance and the 500 ohm high voltage resistor). The energy from a 1000 volt (100 pF) discharge shall be 50 J

49、 ( 6 J). This is obtained from the equation E = 1/2 CV2. 7.0 SYSTEM VERIFICATION PROCEDURE A) Connect the 500 ohm resistor between the two conductive plates of the capacitive probe. Place the capacitive probe between the discharge and ground electrodes. Ensure that the discharge electrode, the capacitive probe and the ground electrode are vertically aligned and that there is good contact between all three elements. B) Connect the current probe to the storage oscilloscope. Set the oscilloscope input resistance to 50 ohms. C) Set the horizontal time