ANSI ESD S541-2008 Packaging Materials for ESD Sensitive Items.pdf

1、 ANSI/ESD S541-2008 Reaffirmation of ANSI/ESD S541-2003 For the Protection of Electrostatic Discharge Susceptible Items Packaging Materials for ESD Sensitive Items Electrostatic Discharge Association 7900 Turin Road, Bldg. 3 Rome, NY 13440-2069 An American National Standard Approved September 29, 20

2、08ANSI/ESD S541-2008 ESD Association Standard for the Protection of Electrostatic Discharge Susceptible Items Packaging Materials for ESD Sensitive Items Approved June 8, 2008 ESD Association, Inc. ANSI/ESD S541-2008 Electrostatic Discharge Association (ESDA) standards and publications are designed

3、to serve the public interest by eliminating 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

4、publications shall not in any respect 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 is published by the Association preclude its voluntary use by non-mem

5、bers of the Association whether 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. CAUTION NOTICE Interpretation of ESDA Standards: The interpretation of standards in-so-far as i

6、t may relate to a specific product or manufacturer 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

7、 standard, but not related to its application 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, EXPRESS O

8、R IMPLIED, OF ANY KIND WITH RESPECT TO SUCH CONTENTS. ESDA DISCLAIMS ALL REPRESENTATIONS AND WARRANTIES, INCLUDING WITHOUT LIMITATION, WARRANTIES OF MERCHANTABILITY, FITNESS FOR PARTICULAR PURPOSE OR USE, TITLE AND NON-INFRINGEMENT. DISCLAIMER OF WARRANTIES ESDA STANDARDS AND PUBLICATIONS ARE CONSID

9、ERED TECHNICALLY SOUND AT THE TIME THEY ARE APPROVED FOR PUBLICATION. 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 GUARANTY THE PERFORMANCE OF ANY INDIVIDUAL MANUFACTURERS PRODUCTS BY VIRTUE OF

10、 SUCH STANDARDS OR PUBLICATIONS. THUS, ESDA EXPRESSLY DISLAIMS ANY RESPONSIBILITY FOR DAMAGES ARISING FROM THE USE, APPLICATION, OR RELIANCE BY OTHERS ON THE INFORMATION CONTAINED IN THESE STANDARDS OR PUBLICATIONS. DISCLAIMER OF GUARANTY NEITHER ESDA, NOR ITS MEMBERS, OFFICERS, EMPLOYEES OR OTHER R

11、EPRESENTATIVES WILL BE LIABLE FOR DAMAGES ARISING OUT OF OR IN CONNECTION WITH THE USE OR MISUSE OF ESDA STANDARDS OR PUBLICATIONS, EVEN IF ADVISED OF THE POSSIBILITY THEROF. THIS IS A COMPREHENSIVE LIMITATION OF LIABILITY THAT APPLIES TO ALL DAMAGES OF ANY KIND, INCLUDING WITHOUT LIMITATION, LOSS O

12、F DATA, INCOME OR PROFIT, LOSS OF OR DAMAGE TO PROPERTY AND CLAIMS OF THIRD PARTIES. LIMITATION ON ESDAs LIABILITY Published by: Electrostatic Discharge Association 7900 Turin Road, Bldg. 3 Rome, NY 13440 Copyright 2008 by ESD Association All rights reserved No part of this publication may be reprod

13、uced in any form, in an electronic retrieval system or otherwise, without the prior written permission of the publisher. Printed in the United States of America ISBN: 1-58537-149-1ANSI/ESD S541-2008 FOREWORD Packaging is necessary to protect electronic items from physical and environmental damage du

14、ring manufacture, transportation, and storage. While most types of packaging (not for static sensitive items) provide physical and environmental protection, it also may harm static sensitive electronic items by allowing the accumulation or the discharge of static electricity. (See Annex B for device

15、 damage information.) Packaging for ESD sensitive items is commonly derived by modifying existing packaging to prevent the packaging itself from causing static damage. The packaging generally retains its physical and environmental protective qualities. ESD protective packaging has been modified furt

16、her to prevent other sources of static electricity from damaging a packaged item. This can be illustrated by considering bags. Polyethylene bags are useful packages for containing items and providing protection from physical and environmental damage. However, polyethylene bags accumulate potentially

17、 damaging amounts of static electricity. Chemicals (antistats) are added to the polyethylene bag to render it low charging. The result is a low charging (antistatic) polyethylene bag that is less likely to damage static sensitive items. By adding a conductive layer to the low charging polyethylene b

18、ag, an ESD shielding bag is created. This shielding bag is low charging, and shields packaged items from ESD and the electric field generated by other items. Other standard packaging including paper corrugate and plastic boxes, trays, and clamshells have, or are presently, following similar paths. A

19、 complete ESD control program, as defined by ANSI/ESD S20.20, requires the use of ESD protective packaging to properly manufacture, transport, and store ESD sensitive devices. This Standard provides requirements for ESD protective packaging that must be included inside and outside an Electrostatic P

20、rotected Area (EPA). Because most physical and environmental considerations can be left to traditional packaging design and testing methodologies, only the material properties that provide reduction or prevention of damage from static electricity need be addressed. This standard describes the packag

21、ing material properties needed to protect electrostatic discharge (ESD) sensitive electronic items, and references the testing methods for evaluating packaging and packaging materials for those properties. Where possible, performance limits are provided. Guidance for selecting the types of packaging

22、 with protective properties appropriate for specific applications is provided. Other considerations for protective packaging are also provided. This document is a substantial refinement of the discontinued Electronic Industries Association Standard EIA-541-1988. Updates include the adoption of surfa

23、ce resistance (ohms) in place of surface resistivity (ohms/square), volume resistance (ohms) in place of volume resistivity (ohm-cm), a shielding test that allows penetrating energy (nanoJoules) to be calculated in place of a voltage measurement (volts), and limits the use of static decay testing. R

24、esistance is no longer the only property that is used to classify ESD packaging. Low Charging, Electric Field Shielding and Direct Discharge Shielding have been added. i ANSI/ESD S541-2008 This standard was originally designated ANSI/ESD S541-2003 and was approved on February 9, 2003. Standard ANSI/

25、ESD S541-2008 is a reaffirmation of ANSI/ESD S541-2003 and was approved on June 8, 2008. Both documents were prepared by the 11.0 Packaging Subcommittee. At the time the 2003 version was prepared, the 11.0 Packaging Subcommittee has the following members: Brent Beamer, Chairman Static Control Compon

26、ents, Inc. Joe Blanchard Bradford Company Walt Gately Gately Ph: 315-339-6937; FAX: 315-339-6793; www.esda.org 2Naval Air Warfare Center Aircraft Division, Highway 547, Lakehurst, NJ 08733-5100 ANSI/ESD S541-2008 5.0 PERSONNEL SAFETY The procedures and equipment described in this document may expose

27、 personnel to hazardous 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

28、safety. Ground fault 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 shall be followed. 6.0 PACKA

29、GING APPLICATION REQUIREMENTS Transportation of electrostatic sensitive devices requires packaging that provides protection from electrostatic hazards in the transportation or storage system. In the case of an EPA designed with continuous grounding of all conductors and dissipative items (including

30、personnel), packaging may not be necessary. Refer to Table 1, Figures 1 and 2, and Annex A for more information. 6.1 Inside an EPA Packaging used within an EPA (that satisfies the minimum requirements of ANSI/ESD S20.20) shall be: Low charge generation. Dissipative or conductive materials for intima

31、te contact. Items sensitive to 104 to 1011ANSI/ESD S541 Figure 3: Resistance Classifications 7.3 Static Shielding Property Electrostatic shielding materials protect packaged sensitive electronic items from the effects of static electricity that are external to the package. 7.3.1 Electrostatic Discha

32、rge Shielding Electrostatic discharge shielding materials are capable of attenuating an electrostatic discharge when formed into a container. The calculated energy allowed inside a static discharge shielding bag shall be less than 50 nanojoules when tested according to Table 3. ANSI/ESD S541-2008 7.

33、3.2 Electric Field Shielding Electric field shielding materials are capable of attenuating an electric field when formed into a container. NOTE: Field-shielding materials classified according to section 7.2.1.1 may allow current flow through their volume. 8.0 ESD PACKAGING TECHNICAL REQUIREMENTS Pac

34、kaging shall be defined for all material movement inside and outside electrostatic protected areas (EPA). 8.1 Material Properties Table 3 provides test methods for determining material classifications for finished packages and materials. When possible, testing should be performed on the finished pac

35、kage. 8.2 Material Identification 8.2.1 Warning Symbol ESD protective packaging shall be marked with the ESD protective symbol as described in ANSI/ESD S8.1, or MIL-STD-2073 for military applications. 8.2.2 Material Classification ESD protective packaging should be marked with the proper material cl

36、assification per Section 7.0 as: Charge Generation: “Low Charging” (preferred) or “Antistatic” Resistance: “Conductive” or “Dissipative” Shielding: “Discharge Shielding” or “Electric field Shielding” Use of multiple classifications is acceptable. 8.2.3 Traceability Packaging should be marked with in

37、formation that allows traceability to the packaging manufacturer and to the manufacturers date/lot code information. The date/lot code should allow traceability to quality control information pertaining to the manufacture of the specific lot of packaging. 7 ANSI/ESD S541-2008 Table 3. Test Methods f

38、or Electrostatic Protective Packaging Material Property Test Method Method Description Limits Low Charging (Antistatic) ESD ADV11.2 Tribocharging of tubes, planar materials, bags, unit packs (vibration) User defined Resistance ANSI/ESD STM11.11 Surface resistance of planar materials 104to 104to 104t

39、o 1011ohms Shielding ANSI/ESD STM11.31 ESD Shielding of Bags 50 nanojoules 8 ANSI/ESD S541-2008 ANNEX A (INFORMATIVE) ESD PACKAGING MATERIAL GUIDANCE A.1 Environment and Device Sensitivity Environment and device sensitivity are two primary considerations for selecting ESD packaging material properti

40、es. A.1.1 Environment Since the threat to a sensitive item is usually undetermined when the item is outside an ESD protected area (EPA), ESD sensitive items should be placed in ESD protective packaging whenever the item is outside the EPA or needs physical and environmental protection within the EPA

41、. A.1.2 Device Sensitivity If the items sensitivity is unknown, it should be packaged in a manner that provides all of the protective properties. By understanding these factors, the level of static protective properties may be reduced: Device sensitivity to ESD and ESD effects. ESD threats that devi

42、ce will experience. Then the device should be evaluated for damage from those ESD threats, while being protected by the proposed level of packaging. A.2 Equipotential Bonding While not always recognized as being a packaging consideration, equipotential bonding, or the shunting of leads, can be an ef

43、fective method to mitigate damage. By placing a conductive shunt across device leads or card connectors, the various parts of the item share the same electrical potential. While not necessarily at ground potential, the fact that parts of the item share the same potential means that damaging current

44、will not flow between them. Shunting has limitations. Energy from direct discharge and electric fields may impact the item in a manner that does not allow the energy to equalize through the shunt, but instead through the device. ESD packaging that offers other protective properties is usually used i

45、n conjunction with shunting devices. NOTE: Care should be exercised to neutralize charge on devices prior to shunting to avoid charged device model (CDM) damage. See Annex B for more information. A.3 Dissipative Material for Intimate Contact To avoid rapid discharge to sensitive items, dissipative m

46、aterials should be used as the layer of packaging that contacts the item. A.4 ESD Packaging Types Many forms of packaging are available with electrostatic protective properties. This includes packaging such as bags, boxes (paperboard and plastic), semi-rigid plastic trays, cushion wrap, foam, loose

47、fill, tape, trays, tubes, tape and reel, shrink-wrap, and stretch-wrap. Refer to Annex E for additional information. 9 ANSI/ESD S541-2008 A.5 Packaging from Incoming Material to the Point of Use Figure 1 shows a simplified layout of a generic electronic packaging application. Each area has the recom

48、mended ESD packaging material properties noted. As discussed in Section A.1.2, if the item sensitivity and threats are documented, the level of ESD packaging can be reduced after confirming packaging functionality. NOTE: This layout shows an “islands of protection” approach to ESD safeguards. Many m

49、anufacturing processes employ a “total factory” approach, where the entire factory is a safeguarded area. A.6 Compliance Verification The static control properties of some packaging materials can deteriorate with time and use. Compliance Verification of static control packaging properties should be part of the ESD control compliance verification plan. A.7 Other Considerations A7.1 ESD Control Program ESD packaging alone cannot protect ESDS devices. It is but one component of the comprehensive ESD control program described in ANSI/ESD S20.20. A7.2 Contamin