With the destabilization of the economy, many companies are looking for ways to increase profits and performance within their particular industry. The electronics industry is no exception. Many electronics companies are working towards improved quality and reliability at the same rate as improving the performance of the products they manufacture.
The ESD Association released an ESD Technology Road Map in 2005 and is currently updating it for current trends in an effort to create awareness within the global electronics industry of changes that were, and are, right around the corner. The Road Map pointed out that numerous mainstream electronic parts and components would reach assembly factories with a lower level of ESD protection than could have been expected just a few years earlier. This prediction in the Road Map has come true. The manufacturing industry may have become a bit complacent in the past few years since many design schemes offered very good levels of ESD protection. However, the ever increasing demands for enhanced performance, speed, storage capacity, bandwidth, and an increasing scale of integration has led to a significant reduction of on-chip protection. This, combined with an increase in physical package size, has exacerbated the ESD damage issue in the manufacturing environment. Nowhere is this more evident than in the world of wireless communication devices and other portable electronic equipment. The features crammed into a pocket sized cell phone are truly amazing and many more features are on the way. As consumers demand and are granted more features and higher performance, manufacturers must adapt to handling increased ESD susceptibility in their parts.
The ESD Association Standards Committee is charged with keeping pace with the industry demands for increased performance. The existing Standards, Standard Test Methods, Standard Practices, and Technical Reports assist in the design and monitoring of the Electrostatic Protected Area (EPA), and also assist in the testing of ESD sensitive electronic components. Many of the existing documents relate to controlling electrostatic charge on personnel and stationary work areas. However, with the ever increasing emphasis on automated handling, the need to evaluate and monitor what is occurring inside of process equipment is growing daily. In the typical factory, a shift is being made from Human Body Model device susceptibility as the major concern, to Charge Device Model considerations.
One major effort that the ESD Association Standards Committee has undertaken is a joint document development activity with JEDEC. JEDEC Solid State Technology Association and the ESD Association entered into a Memorandum of Understanding for the development of joint standards and publications in the field of device electrostatic discharge (ESD) sensitivity testing. Under the agreement, the ESD Association and JEDEC have formed a Joint Task Force for the standardization work in which volunteers from the ESD Association and JEDEC member companies can participate. This collaboration between the ESDA and JEDEC has paved the way for the development of harmonized test methods for ESD, which will ultimately reduce uncertainty about test standards among manufacturers and suppliers
in the solid state industry. At the time of this publication,
ESDA/JEDEC JDS-001-2010, a joint HBM document, is being released for distribution. This document will replace ANSI/ESD S5.1-2007 and JEDEC JESD22-A114F, the current industry test methods and specifications for Human Body Model device testing. A second joint committee is currently working on a joint Charged Device Model (CDM) document with a goal of publishing in 2011. These efforts will assist manufacturers of devices by providing one test method and specification instead of multiple, almost – but not quite identical, versions of device testing methods.
There is no question that the existing ESD Association Standards such as ANSI/ESD S20.20 (Program Development) and ANSI/ESD S541 (Packaging for Shipment) are important to industry. These documents are downloaded from www.esda.org in excess of 1,000 times per month on average, and it is expected that the new joint device testing documents will be in similar demand. Additionally, the ESD Technology Road Map has had approximately 26,000 downloads from 2006 to 2009. The industry is paying attention.
The factory Certification Bodies report strong interest in Certification to S20.20, and the world of consultants in this area report that inquiries for assistance remain at a very high level. Individual education also seems of interest once again as 46 professionals have obtained Certified ESD Program Manager status and many more are attempting to qualify as Certified ESD Control Program Managers.
A large percentage of the certification program requirements are based on Standards and the other related documents produced by the ESD Association Standards Committee.
Who Uses ESD Standards and Why?
The list of users of ESD Standards is quite broad; manufacturers, purchasers, and users of ESD sensitive devices and products, manufacturers and distributors of ESD control products, certification bodies, and third party testers of ESD control products.
The reasons to use ESD Standards are numerous:
They help assure consistency of the reported susceptibility of ESD sensitive products.
They help assure consistency of ESD control products and services.
They provide a means of objective evaluation and comparison among competitive ESD control products.
They help reduce conflicts between users and suppliers of ESD control products.
They help in developing, implementing, auditing, and certifying ESD control programs.
They help reduce confusion in the marketplace.
In the United States the use of ESD standards continues to be voluntary. However, their use can be written into contracts or purchasing agreements between buyer and seller. In much of the rest of the world the use of standards, where they exist, is compulsory.
General Types of Standards
As recently as 1990 there were relatively few reliable ESD standards, and many of them were developed for applications other than electronics. In this new century the landscape has changed significantly, with an increasing number of ESD standards developed specifically for the electronics industry.
ESD Association standards can be categorized into four main groups.
First, there are those documents that provide ESD program guidance or requirements. These documents are classified as standards (S), as they all have specific requirements that must be met.
Examples of standards are:
ANSI/ESD S20.20-2007 Protection of Electrical and Electronic Parts, Assemblies and Equipment (Excluding Electrically Initiated Explosive Devices)
ANSI/ESD S6.1-2009 Grounding; and
ANSI/ESD S541-2008 Packaging Materials for
ESD Sensitive Items.
The second document category is classified as standard test methods (STM). These documents contain procedures that can be used to evaluate device sensitivity or ESD control products, materials, or processes. The procedures called out in a standard test method should provide reproducible test results when tested by two separate labs.
Examples of standard test methods are:
ANSI/ESD STM3.1-2006 Ionization
ANSI/ESD STM5.5.1-2008 Sensitivity Testing – Transmission Line Pulse (TLP) – Component Level
The third document category is classified as a standard practice (SP). A standard practice contains content similar to those found in a standard test method, but a standard practice is not sufficiently developed to ensure that two labs will get the same result when the procedure is followed. In many cases a standard practice is released so that industry can begin to use it, while the working group continues their efforts (to make the test method repeatable and reproducible) with the goal of potentially elevating the document to a standard test method.
Examples of standard practices are:
ANSI/ESD SP10.1-2007 Automated Handling
Equipment (AHE)
ANSI/ESD SP5.6-2009 Sensitivity Testing Human
Metal Model – Component Level
The last category of standards documents include advisories and technical reports. These types of documents are used to provide educational information to the industry.
Examples of advisories (ADV) and technical reports (TR) are:
TR20.20, ESD Handbook. This document is a companion publication to ANSI/ESD S20.20 and provides detailed background information on the requirements of the standard, as well as a wealth of information on ESD control issues.
ESD ADV1.0, Glossary of Terms. This document lists definitions and explanations of various terms used in Association Standards and documents. It also includes other terms commonly used in the electronics industry.
Who Are the Primary Standards Developers?
Although there are a number of organizations such as IEST, IDEMA, SEMI, and JEDEC involved in ESD standards development, the ESD Association Standards Committee (an ANSI-accredited standards development organization) has become the focal point for the development of ESD standards in the industry. The ESD Association also represents the United States on the International Electrotechnical Commission’s Technical Committee 101-Electrostatics. The ESD Association has currently published 35 standards documents, 23 technical reports and 3 advisory documents covering material and program requirements, electrostatic device sensitivity, and test methodology for evaluating ESD control materials and products.
The International Electrotechnical Commission (IEC) has adopted 5 ESD documents. These documents have been published as follows:
ANSI/ESD S1.1-2006 Wrist Straps
ANSI/ESD STM3.1-2006 Ionization
ANSI/ESD STM11.31-2006 Bags
ANSI/ESD STM2.1-1997 Garments
This document has been submitted at the TC47 Committee Draft for Vote (CDV) level:
ANSI/ESD SP5.5.1-2008 Electrostatic Discharge Sensitivity Testing Transmission Line Pulse (TLP) Component Level
Traditionally, the U.S. military has spearheaded the development of specific standards and specifications with regard to ESD control in the United States. Today, however, U.S. military agencies are taking a less proactive approach, relying on commercially developed standards rather than developing standards themselves. OMB Circular A119 is a directive that was given by the United States government to other government agencies to use voluntary consensus standards instead of rule-making.
The international community, led by the International Electrotechnical Commission (IEC), has also taken an active role in standards development. Europe’s CENELEC has issued a European electrostatic standard, EN 61340-5-1 Protection of Electronic Devices from Electrostatic Phenomena – General Requirements, that was adopted as a European Norm.
Summary
The technical and manufacturing communities will need to monitor processes to make sure they are capable of handling parts with greater ESD sensitivity than they have had to deal with in recent years. Keeping up with the changes in the electronics industry is a task that the ESD Association Standards Committee must face on nearly a daily basis – a daunting task for a volunteer organization.
The ESD Association is the largest industry group dedicated to advancing the theory and the practice of ESD avoidance, with more than 1,500 members worldwide. Readers can learn more about the association and its work at www.esda.org. n
Standards from the ESD Association are available by contacting:
ESD Association, 7900 Turin Road, Building 3, Rome, NY 13440; Phone: 315-339-6937; fax: 315-339-6793;
e-mail: info@esdsa.org; website: www.esda.org.
References
“ESD Control: A Profitable Opportunity in Tight Economic Times,” Stephen A. Halperin, Threshold, January/February 2003, (Rome, NY: ESD Association) pp8-9.
“ESD Standards: An Annual Progress Report,”
Dave Swenson, Conformity, May 2006.
“ESD Standards: An Annual Progress Report,”
Carl Newberg, Conformity Annual Guide 2008.
Current ESD Association Standards Committee Documents
ANSI/ESD S1.1-2006 Wrist Straps
This document establishes test methods for evaluating the electrical and mechanical characteristics of wrist straps. It includes improved test methods and performance limits for evaluation, acceptance, and functional testing of wrist straps.
ESD DSTM2.1-2009 Garments
This standard test method provides test methods for measuring the electrical resistance of garments used to control electrostatic discharge. It covers procedures for measuring sleeve-to sleeve and point-to-point resistance.
ANSI/ESD STM3.1-2006 Ionization
Test methods and procedures for evaluating and selecting air ionization equipment and systems are covered in this standard test method. The document establishes measurement techniques to determine ion balance and charge neutralization time for ionizers.
ANSI/ESD SP3.3-2006 Periodic Verification of Air Ionizers
This standard practice provides test methods and procedures for periodic verification of the performance of air ionization equipment and systems (ionizers).
ANSI/ESD S4.1-2006 Worksurfaces –
Resistance Measurements
This standard establishes test methods for measuring the electrical resistance of worksurface materials used at workstations for protection of ESD susceptible items. It includes methods for evaluating and selecting materials.
ANSI/ESD STM4.2-2006 ESD Protective Worksurfaces – Charge Dissipation Characteristics
This standard test method provides a test method to measure the electrostatic charge dissipation characteristics of worksurfaces used for ESD control.
ANSI/ESD STM5.1-2007 Electrostatic Discharge Sensitivity Testing – Human Body Model (HBM) Component Level
This standard test method updates and revises an existing standard. It establishes a procedure for testing, evaluating and classifying the ESD sensitivity of components to the defined Human Body Model (HBM).
ANSI/ESD SP5.1.1-2006 Human Body Model (HBM) and Machine Model (MM) Alternative Test Method: Supply Pin Ganging – Component Level
This standard practice (SP) document establishes an alternative test method (Supply Pin Ganging) to perform Human Body Model (HBM) or Machine Model (MM) component level ESD tests when the component or device pin count exceeds the ESD Simulator tester channels.
ANSI/ESD SP5.1.2-2006 Human Body Model (HBM) and Machine Model (MM) Alternative Test Method: Split Signal Pin – Component Level
This standard practice (SP) document establishes an alternative test method (Split Signal Pin) to perform Human Body Model (HBM) or Machine Model (MM) component level ESD tests when the component or device pin count exceeds the ESD Simulator tester channels.
ANSI/ESD S5.2-2009 Electrostatic Discharge Sensitivity Testing – Machine Model (MM) Component Level
This standard test method establishes a test procedure for evaluating the ESD sensitivity of components to a defined machine model (MM). It also provides a system of classifying the sensitivity of these components.
ANSI/ESD S5.3.1-2009 Charged Device Model (CDM) – Component Level
This standard test method establishes the procedures for testing, evaluating, and classifying the ESD sensitivity components to a defined charged device model.
ANSI/ESD SP5.3.2-2008 Sensitivity Testing Socketed Device (SDM) Component Level
This standard practice provides a test method for generating a “Socketed Device Model” (SDM) test on a component integrated circuit (IC) device.
ANSI/ESD SP5.4-2008 Transient Latch-up Testing – Component Level Supply Transient Stimulation
This standard practice was developed to instruct the reader on the methods and materials needed to perform transient latch-up testing.
ANSI/ESD STM5.5.1-2008 Electrostatic Discharge Sensitivity Testing Transmission Line Pulse (TLP) Component Level
This standard practice defines a method for pulse testing to evaluate the voltage current response of the component under test.
ANSI/ESD SP5.5.2-2007, Electrostatic Discharge Sensitivity Testing – Very Fast Transmission Line Pulse (VF-TLP) – Component Level
This document pertains to very fast transmission line pulse (VF-TLP) testing techniques of semiconductor components. It establishes guidelines and standard practices presently used by development, research, and reliability engineers in both universities and industry for VF-TLP testing. This document explains a methodology for both testing and reporting information associated with VF-TLP testing.
ANSI/ESD S6.1-2009 Grounding
This standard specifies the parameters, materials, equipment and test procedures necessary to choose, establish, vary and maintain an Electrostatic Discharge Control grounding system for use within an ESD Protected area for protection of ESD susceptible items, and specifies the criteria for establishing ESD Bonding.
ANSI/ESD S7.1-2005 Resistive Characterization of Materials – Floor Materials
Measurement of the electrical resistance of various floor materials such as floor coverings, mats, and floor finishes is covered in this document.
ANSI/ESD S8.1-2007 Symbols – ESD Awareness
Three types of ESD awareness symbols are established by this document. The first symbol is to be used on a device or assembly to indicate that it is susceptible to electrostatic charge. The second symbol is to be used on items and materials intended to provide electrostatic protection. The third symbol indicates the common point ground.
ANSI/ESD STM9.1-2006 Footwear –
Resistive Characterization
This standard defines a test method for measuring the electrical resistance of shoes used for ESD control in the electronics environment. A companion document covering foot grounders is in the draft stage.
ESD SP9.2-2003 Footwear – Foot Grounders Resistive Characterization (not to include static control shoes)
This standard practice was developed to provide test methods for evaluating foot grounders and foot grounder systems used to electrically bond or ground personnel as part of an ESD Control Program. Static control shoes are tested using ANSI/ESD STM9.1.
ANSI/ESD SP10.1-2007 Automated Handling
Equipment (AHE)
This standard practice provides procedures for evaluating the electrostatic environment associated with automated handling equipment.
ANSI/ESD STM11.11-2006 Surface Resistance Measurement of Static Dissipative Planar Materials
This standard defines a direct current test method for measuring electrical resistance of static dissipative planar materials used in packaging of ESD sensitive devices and components.
ANSI/ESD STM11.12-2007 Volume Resistance Measurement of Static Dissipative Planar Materials
This standard test method provides test methods for measuring
the volume resistance of static dissipative planar materials used in the packaging of ESD sensitive devices and components.
ESD DSTM11.13-2009 Two Point Resistance Measurement
This standard test method measures the resistance between two points on a materials’ surface without consideration of the materials’ means of achieving conductivity. This test method was established for measuring resistance where the concentric ring electrodes of ESD Standard Test Method 11.11 cannot be used.
ANSI/ESD STM11.31-2006 Bags
This standard provides a method for testing and determining the shielding capabilities of electrostatic shielding bags.
ANSI/ESD STM12.1-2006 Seating – Resistive Measurement
This standard provides test methods for measuring the electrical resistance of seating used to control ESD.
ESD STM13.1-2000 Electrical Soldering/Desoldering
Hand Tools
This standard test method provides electric soldering/desoldering hand tool test methods for measuring the electrical leakage and tip to ground reference point resistance, and provides parameters for EOS safe soldering operation.
ANSI/ESD SP14.1-2004 System Level Electrostatic Discharge (ESD) Simulator Verification
This standard practice was developed to provide guidance to designers, manufacturers, and calibration facilities for verification and specification of the systems and fixtures used to measure simulator discharge currents.
ESD SP14.3-2009 System Level Electrostatic Discharge (ESD) Measurement of Cable Discharge Current
This standard describes a system for making measurements of the discharge current from charged cables and verifying that the system bandwidth is adequate for capturing the fast initial spike that is known to exist at the beginning of the discharge.
ANSI/ESD SP15.1-2005 In-Use Resistance Testing of Gloves and Finger Cots
This standard practice provides test procedures for measuring the intrinsic electrical resistance of gloves and finger cots.
ANSI/ESD S20.20-2007 Protection of Electrical and Electronic Parts, Assemblies and Equipment
(Excluding Electrically Initiated Explosive Devices)
This standard provides administrative, technical requirements and guidance for establishing, implementing, and maintaining an ESD Control Program.
ANSI/ESD STM97.1-2006 Floor Materials and Footwear – Resistance Measurement in Combination with a Person
This standard test method provides for measuring the electrical resistance of floor materials, footwear and personnel together, as a system.
ANSI/ESD STM97.2-2006: Floor Materials and Footwear – Voltage Measurement in Combination with a Person
This standard test method provides for measuring the electrostatic voltage on a person in combination with floor materials and footwear, as a system.
ANSI/ESD S541-2008 Packaging Materials for
ESD Sensitive Items
This standard defines the packaging properties needed to protect electrostatic discharge sensitive (ESDS) electronic items through all phases of production, transport and storage. The document discusses application requirements and references the testing methods for evaluating packaging and packaging materials for those properties.
Current ESD Association Standards Committee Advisory Documents
ESD Association Advisory documents are not standards, but they provide general information for the industry as well as additional information to aid in better understanding of association standards.
ESD ADV1.0-2009 Glossary of Terms
Definitions and explanations of various terms used in Association Standards and documents are covered in this Advisory. It also includes other terms commonly used in the electronics industry.
ESD ADV11.2-1995 Triboelectric Charge
Accumulation Testing
The complex phenomenon of triboelectric charging is discussed in this Advisory. It covers the theory and effects of tribocharging and it reviews procedures and problems associated with various test methods that are often used to evaluate triboelectrification characteristics.
ESD ADV53.1-1995 ESD Protective Workstations
This advisory document defines the minimum requirements for a basic ESD protective workstation used in ESD sensitive areas. It provides a test method for evaluating and monitoring workstations.
Current ESD Association Standards Committee Technical Reports
ESD TR1.0-01-01, Survey of Constant (Continuous) Monitors for Wrist Straps
ESD TR2.0-01-00, Consideration for Developing ESD Garment Specifications
ESD TR2.0-02-00, Static Electricity Hazards of Triboelectrically Charged Garments
ESD TR3.0-01-02 Alternate Techniques for Measuring Ionizer Offset Voltage and Discharge Time
ESD TR3.0-02-05, Selection and Acceptance of Air Ionizers
ESD TR4.0-01-02, Survey of Worksurfaces and Grounding Mechanisms
ESD TR5.2-01-01, Machine Model (MM) Electrostatic Discharge (ESD) Investigation – Reduction in Pulse Number and Delay Time
ESD TR5.3.2-01-00, Socket Device Model (SDM) Tester
ESD TR5.4-01-00, Transient Induced Latch-Up (TLU)
ESD TR5.4-02-08, Determination of CMOS Latch-up Susceptibility – Transient Latch-up – Technical Report No. 2
ESD TR5.5-01-08 Transmission Line Pulse (TLP)
ESD TR5.5-02-08 Transmission Line Pulse Round Robin
ESD TR5.6-01-09, Human Metal Model (HMM)
ESD TR10.0-01-02, Measurement and ESD Control Issues for Automated Equipment Handling of ESD Sensitive Devices below 100 Volts
ESD TR13.0-01-99, EOS Safe Soldering Iron Requirements
ESD TR14.0-01-00, Calculation of Uncertainty
Associated with Measurement of Electrostatic Discharge (ESD) Current
ESD TR15.0-01-99, ESD Glove and Finger Cots
ESD TR 20.20-2008, ESD Handbook
ESD TR50.0-01-99, Can Static Electricity be Measured?
ESD TR50.0-02-99, High Resistance Ohmmeters – Voltage Measurements
ESD TR50.0-03-03, Voltage and Energy Susceptible Device Concepts, Including Latency Considerations
ESD TR53-01-06 Compliance Verification of ESD Protective Equipment and Materials
ESD TR55.0-01-04, Electrostatic Guidelines and Considerations for Cleanrooms and Clean Manufacturing
