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The electronics industry is continually shifting. Device density and technology is more complex. Electronics manufacturing is more heavily reliant on out-sourcing. The ESD industry seems to have jumped into this swirling eddy headfirst. ESD control programs have mushroomed. Black has been replaced by green, blue and gold. Shielding bags dominate the warehouse. Ionizers exist along side wrist straps and ground cords. An early history of “smoke and mirrors,” magic and lofty claims of performance is rapidly and safely being relegated to the past.

Today, more than ever, meeting the complex challenge of reducing ESD losses requires more than reliance on faith alone. Users require a way to legitimately evaluate and compare competing brands and types of products. They need objective confirmation that their ESD control program provides effective solutions to their unique ESD problems. Contract manufacturers and OEM’s require mutually agreed-upon ESD control programs that reduce duplication of process controls.

That’s where standards come into play. They provide guidance in developing programs that effectively address ESD process control. They help define the sensitivity of the products manufactured and used. They help define the performance requirements for various ESD control materials, instruments, and tools. Standards are playing an ever-increasing role in reducing marketplace confusion in the manufacture, evaluation, and selection of ESD control products and programs.

The Who and Why of Standards

Who uses ESD standards? Manufacturers and users of ESD sensitive devices and products, manufacturers and distributors of ESD control products, certification registrars, and third party testers of ESD control products.

Why use ESD standards? They help assure consistency of ESD sensitive products and 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. And, they help reduce confusion in the marketplace.

In the United States, the use of standards is voluntary, although their use can be written into contracts or purchasing agreements between buyer and seller. In most of the rest of the world, the use of standards, where they exist, is compulsory.

Key Standards and Organizations

Just 20 years ago, there were relatively few reliable ESD standards and few ESD standards development organizations. Today’s ESD standards landscape is not only witnessing an increase in the number of standards, but also increasing cooperation among the organizations that develop them.

Today’s standards fall into three main groups. First, there are those that provide ESD program guidance or requirements. These include documents such as ANSI ESD S20.20-2007–Standard for the Development of an ESD Control Program, ANSI/ESD S8.1-Symbols-ESD Awareness , or ESD TR20.20-ESD Handbook.

A second group covers requirements for specific products or procedures such as packaging requirements and grounding. Typical standards in this group are ANSI/ESD S6.1-Grounding and ANSI/ESD S541 –Packaging Materials for ESD Sensitive Items.

A third group of documents covers the standardized test methods used to evaluate products and materials. Historically, the electronics industry relied heavily on test methods established for other industries or even for other materials (e. g., ASTM-257-DC Resistance or Conductance of Insulating Materials). Today, however, specific test method standards focus on ESD in the electronics environment, largely as a result of the ESD Association’s activity. These include standards such as ANSI/ESDA-JEDEC JS-001-2010-Device Testing, Human Body Model and ANSI/ESD STM7.1: Floor Materials — Resistive Characterization of Materials to cite just a few.

Who Develops Standards?

Standards development and usage is a cooperative effort among all organizations and individuals affected by standards. There are several key ESD standards development organizations.

Military Standards

Traditionally, the U.S. military spearheaded the development of specific standards and specifications with regard to ESD control in the U.S. Today, however, U.S. military agencies are taking a less proactive approach, relying on commercially developed standards rather than developing standards themselves. For example, the ESD Association completed the assignment from the Department of Defense to convert MIL-STD-1686 into a commercial standard called ANSI/ESD S20.20.

ESD Association

The ESD Association has been a focal point for the development of ESD standards in recent years. An ANSI-accredited standards development organization, the Association is charged with the development of ESD standards and test methods. The Association also represents the US on the International Electrotechnical Commission (IEC) Technical Committee 101-Electrostatics.

The ESD Association has published 36 standards documents and 23 Technical Reports. These voluntary standards cover the areas of material requirements, electrostatic sensitivity, and test methodology for evaluating ESD control materials and products. In addition to standards documents, the Association also has published a number of informational advisories. Advisory documents may be changed to other document types in the future.

ESD Association Standards Classifications and Definitions

There are four types of ESD Association standards documents with specific clarity of definition. The four document categories are consistent with other standards development organizations. These four categories are defined below.

• Standard: A precise statement of a set of requirements to be satisfied by a material, product, system or process that also specifies the procedures for determining whether each of the requirements is satisfied.
• Standard Test Method: A definitive procedure for the identification, measurement and evaluation of one or more qualities, characteristics or properties of a material, product, system or process that yields a reproducible test result.
• Standard Practice: A procedure for performing one or more operations or functions that may or may not yield a test result. Note: If a test result is obtained, it may not be reproducible between labs.
• Technical Report: A collection of technical data or test results published as an informational reference on a specific material, product, system, or process.

As new documents are approved and issued, they will be designated into one of these four new categories. Existing documents have been reviewed and have been reclassified as appropriate. Several Advisory Documents still exist and may be migrated to either Technical Reports or Standard Practices in the future.

International Standards

The international community, led by the European-based International Electrotechnical Commission (IEC), has also climbed on board the standards express. IEC Technical Committee 101 has released a series of documents under the heading IEC 61340. The documents contain general information regarding electrostatics, standard test methods, general practices and an ESD Control Program Development Standard that is technically equivalent to ANSI/ESD S20.20.  A Facility Certification Program is also available.  Global companies can seek to become certified to both ANSI/ESD S20.20 and to IEC61340-5-1 if they so choose. Japan also has released its proposed version of a national electrostatic Standard, which also shares many aspects of the European and U.S. documents.

Organizational Cooperation

Perhaps one of the more intriguing changes in ESD standards has been the organizational cooperation developing between various groups.  One cooperative effort was between the ESD Association and the U.S. Department of Defense, which resulted in the Association preparing ANSI/ESD S20.20 as a successor to MIL-STD-1686.  A second cooperative effort occurred between the ESD Association and JEDEC, which started with an MOU and resulted in the development of 2 documents: a joint HBM document was published in 2010; a joint CDM document will be published in 2011.

Internationally, European standards development organizations and the ESD Association have developed working relationships that result in an expanded review of proposed documents, greater input, and closer harmonization of standards that impact the international electronics community.

For users of ESD standards, this increased cooperation will have a significant impact. First, we should see standards that are technically improved due to broader input. Second, we should see fewer conflicts between different standards. Finally, we should see less duplication of effort.

Summary

For the electronics community, the rapid propagation of ESD standards and continuing change in the standards environment mean greater availability of the technical references that will help improve ESD control programs. There will be recommendations to help set up effective programs. There will be test methods and specifications to help users of ESD control materials evaluate and select products that are applicable to their specific needs. And there will be guidelines for vendors of ESD products and materials to help them develop products that meet the real needs of their customers.

Standards will continue to fuel change in the international ESD community.

Sources of Standards

ESD Association, 7900 Turin Road, Building 3, Rome, NY 13440. Phone: 315-339-6937. Fax: 315-339-6793. Web Site: http://www.esda.org

IHS Global Engineering Documents, 15 Inverness Way East, Englewood, CO 80112. Phone: 800-854-7179. Fax: 303-397-2740. Web Site: http://global.ihs.com

International Electrotechnical Commission, 3, rue de Varembe, Case postale 131, 1211 Geneva 20, Switzerland. Fax: 41-22-919-0300. Web Site: http://www.iec.ch/

Military Standards, Naval Publications and Forms Center, 5801 Tabor Avenue, Philadelphia, PA 19120

JEDEC Solid State Technology Association, 3103 North 10th Street, Suite 240-S
Arlington, VA  22201-2107, http://www.jedec.org

Principle ESD Standards

U.S. Military/Department of Defense

MIL-STD-1686C: Electrostatic Discharge Control Program for Protection of Electrical and Electronic Parts, Assemblies and Equipment (Excluding Electrically Initiated Explosive Devices) This military standard establishes requirements for ESD Control Programs. It applies to U.S. military agencies, contractors, subcontractors, suppliers and vendors. It requires the establishment, implementation and documentation of ESD control programs for static sensitive devices, but does NOT mandate or preclude the use of any specific ESD control materials, products, or procedures. It is being updated and converted to a commercial standard by the ESD Association. Although DOD has accepted the new ANSI/ESD S20.20 document as a successor, it has not yet taken action to cancel STD-1686

MIL-HBDK-263B: Electrostatic Discharge Control Handbook for Protection of Electrical and Electronic Parts, Assemblies and Equipment (Excluding Electrically Initiated Explosive Devices)
This document provides guidance, but NOT mandatory requirements, for the establishment and implementation of an electrostatic discharge control program in accordance with the requirements of MIL-STD-1686.

MIL-PRF 87893—Workstation, Electrostatic Discharge (ESD) Control
This document defines the requirements for ESD protective workstations.

MIL-PRF-81705—Barrier Materials, Flexible, Electrostatic Protective, Heat Sealable
This documents defines requirements for ESD protective flexible packaging materials.

MIL-STD-129—Marking for Shipment and Storage
Covers procedures for marketing and labeling ESD sensitive items.

ESD Association

Standards Documents

ANSI/ESD S1.1: Evaluation, Acceptance, and Functional Testing of Wrist Straps
A successor to EOS/ESD S1.0, 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.

ANSI/ESD STM2.1: Resistance Test Method for Electrostatic Discharge Protective 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-: Ionization 
Test methods and procedures for evaluating and selecting air ionization equipment and systems are covered in this standard. The document establishes measurement techniques to determine ion balance and charge neutralization time for ionizers.

ANSI/ESD SP3.3: 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: 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, and testing new worksurface installations and previously installed worksurfaces.

ANSI/ESD STM4.2: 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. The procedure is designed for use in a laboratory environment for qualification, evaluation or acceptance of worksurfaces.

ESDA-JEDEC  JS-001: Electrostatic Discharge Sensitivity Testing — Human Body Model
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 STM5.2): Electrostatic Discharge Sensitivity Testing — Machine Model
This Standard establishes a test procedure for evaluating the ESD sensitivity of components to a defined Machine Model (MM).  The component damage caused by the Machine Model is often similar to that caused by the Human Body Model, but it occurs at a significantly lower voltage.

ANSI/ESD STM5.3.1: Electrostatic Discharge Sensitivity Testing – Charged Device Model — Non-Socketed Mode
This Standard Test Method establishes a test method for evaluating the ESD sensitivity of active and passive components to a defined Charged Device Model (CDM).

ANSI/ESD SP5.3.2: Electrostatic Discharge Sensitivity Testing. – Socketed Device Method (SDM) – component Level.     
This standard practice provides a test method generating a Socketed Device Model (SDM) test on a component integrated circuit (IC) device.

ANSI/ESD SP5.4:  Latchup Sensitivity Testing of CMOS/BiCMOS Integrated Circuits. – Transient Latchup Testing – Component Level Suppl Transient simulation.
This standard practice method was developed to instruct the reader on the methods and materials needed to perform Transient latchup testing.

ANSI/ESD STM5.5.1:Electrostatic Discharge Sensitivity Testing – Transmission Line Pulse (TLP) – Component Level.
This document pertains to Transmission Line Pulse (TLP) testing techniques of semiconductor components. The purpose of this document is to establish a methodology for both testing and reporting information associated with TLP testing.

ANSI/ESD SP5.5.2: 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 SP5.6:   Electrostatic Discharge Sensitivity Testing – Human Metal Model (HMM) – Component Level
Establishes the procedure for testing, evaluating, and classifying the ESD sensitivity of components to the defined HMM.

ANSI/ESD S6.1: Grounding  
This Standard recommends the parameters, procedures, and types of materials needed to establish an ESD grounding system for the protection of electronic hardware from ESD damage. This system is used for personnel grounding devices, worksurfaces, chairs, carts, floors, and other related equipment.

ANSI ESD S7.1: Floor Materials — Resistive Characterization of Materials 
Measurement of the electrical resistance of various floor materials such as floor coverings, mats, and floor finishes is covered in this document. It provides test methods for qualifying floor materials before installation or application and for evaluating and monitoring materials after installation or application.

ANSI ESD S8.1: ESD Awareness Symbols
Three types of ESD awareness symbols are established by this document. The first one is to be used on a device or assembly to indicate that it is susceptible to electrostatic charge. The second is to be used on items and materials intended to provide electrostatic protection. The third symbol indicates the common point ground

ANSI/ESD S9.1: Resistive Characterization of Footwear
This Standard defines a test method for measuring the electrical resistance of shoes used for ESD control in the electronics environment.

ANSI/ESD SP10.1: Automated Handling Equipment
This Standard Practice provides procedures for evaluating the electrostatic environment associated with automated handling equipment.

ANSI ESD STM11.11: Surface Resistance Measurement of Static Dissipative Planar Materials 
This Standard Test Method defines a direct current test method for measuring electrical resistance. The Standard is designed specifically for static dissipative planar materials used in packaging of ESD sensitive devices and components.

ANSI/ESD STM11.12: 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.

ANSI/ESD STM11.13: Two-Point Resistance Measurement
This Standard Test Method provides a test method to measure the resistance between two points on an items surface.

ANSI ESD STM11.31: Evaluating the Performance of Electrostatic Discharge Shielding Bags 
This Standard provides a method for testing and determining the shielding capabilities of electrostatic shielding bags.

ANSI/ESD STM12.1: Seating-Resistive Characterization
This Standard provides test methods for measuring the electrical resistance of seating used to control ESD. The test methods can be used for qualification testing as well as for evaluating and monitoring seating after installation. It covers all types of seating, including chairs and stools.

ANSI/ESD STM13.1: 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 SP15.1: Standard Practice for In-Use Testing of Gloves and Finger Cots
This document provides test procedures for measuring the intrinsic electrical resistance of gloves and finger cots as well as their electrical resistance together with personnel as a system.

ANSI ESD S20.20: Standard for the Development of an ESD Control Program
This Standard provides administrative, technical requirements and guidance for establishing, implementing and maintaining an ESD Control Program.

ANSI/ESD STM97.1: Floor Materials and Footwear – Resistance 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- 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.

Advisory Documents

Advisory Documents and Technical Reports are not Standards, but provide general information for the industry or additional information to aid in better understanding of Association Standards.

• ESD ADV1.0: 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 ESD industry.
• ESD ADV3.2: Selection and Acceptance of Air Ionizers
  This Advisory document provides end users with guidelines for creating a performance specification for selecting air ionization systems. It reviews four types of air ionizers and discusses applications, test method references, and general design, performance and safety requirements.
• ESD ADV11.2: Triboelectric Charge Accumulation Testing
  The complex phenomenon of triboelectric charging is discussed in this Advisory. It covers the theory and effects of tribocharging. It reviews procedures and problems associated with various test methods that are often used to evaluate triboelectrification characteristics. The test methods reviewed indicate gross levels of charge and polarity, but are not necessarily repeatable in real world situations.
• ESD TR53.1: 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. It defines workstations as having the following components: support structure, static dissipative worksurface, a means of grounding personnel, and any attached shelving or drawers.
• ESD TR 20.20: ESD Handbook
  New handbook provides detailed guidance for implementing an ESD control program in accordance with ANSI/ESD S20.20.

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Your static control program is up and running. How do you determine whether it is effective? How do you make sure your employees follow it? In Part Three, we covered basic static control procedures and materials of your ESD control program.  In Part Four, we will focus on two ESD control program plan requirements: training and compliance verification auditing. Per ANSI/ESD S20.20 and IEC 61340-5-1 the written ESD control plan is to include a training plan and a compliance verification plan.

Personnel Training

The procedures are in place. The materials are in use. But, your ESD control program just does not seem to yield the expected results. Failures declined initially, but they have begun reversing direction. Or perhaps there was little improvement. The solutions might not be apparent in inspection reports of incoming ESD protective materials. Nor in the wrist strap log of test results. In large companies or small, it is hard to overestimate the role of training in an ESD control program. ANSI/ESD S20.20 and IEC 61340-5-1 ESD Control Program standards cite training as a basic administrative requirement within an ESD control program. There is significant evidence to support the contribution of training to the success of the program. We would not send employees to the factory floor without the proper soldering skills or the knowledge to operate the automated insertion equipment. We should provide them with the same skill level regarding ESD control procedures.

Elements of Effective Training Programs

Although individual requirements cause training programs to vary from company to company, there are several common threads that run through the successful programs.

Successful training programs cover all affected employees.

Obviously we train the line employees who handle ESD sensitive devices and typically test their wrist straps or place finished products in static protective packaging. But we also include department heads, upper management, and executive personnel in the process. Typically they are responsible for the day-to-day supervision and administration of the program or they provide leadership and support. Even subcontractors and suppliers should be considered for inclusion in the training program if they are directly involved in handling your ESD sensitive components, sub-assemblies or products. Because ESD control programs cover such a variety of job disciplines and educational levels, it may be necessary to develop special training modules for each organizational entity. For example, the modules developed for management, engineering, assembly technicians and field service could differ significantly from one another because their day-to-day concerns and responsibilities are much different. Also the different education and skills should be considered.

Effective training is comprehensive and consistent.

Training not only covers specific procedures, but also the physics of the problem and the benefits of the program as well. Consistent content across various groups, facilities, and even countries (adjusted for cultural differences) reduces confusion and helps assure conformance. The training content should include topics such as the fundamentals of static electricity and electrostatic discharges, the details of the organization’s ESD Control Program plan, and each person’s role in the plan.

Use a variety of training tools and techniques.

Choose the methods that will work best for your organization. Combine live instruction with training videos or interactive computer-based programs. You may have in-house instructors available, or you may need to go outside the company to find instructors or training materials. You can also integrate industry symposia, tutorials, and workshops into your program. Consider using this “Fundamentals of ESD” series of articles. Effective training involves employees in the process. Reinforce the message with demonstrations of ESD events and their impact. Bulletin boards, newsletters, and posters provide additional reminders and reinforcement. Maintaining a central repository for educational ESD control materials will help your employees keep current or answer questions that may occur outside the formal training sessions. Materials in such a repository might include

• Material from initial and recurring training sessions
• ESD Association or internal bulletins or newsletters
• DVDs or CDs
• Computer based training materials
• Technical papers, studies, standards (e.g. ESD Association, IEC, JEDEC), test methods and technical reports
• ESD control material and equipment product technical data sheets

In addition, a knowledgeable person in the organization should be available to answer trainee questions once they have begun working.

Test, certify and retrain

Your training should assure comprehension, material retention and emphasize the importance of the effort. If properly implemented, testing and certification motivates and builds employee pride. Retraining or refresher training is an ongoing process that reinforces, reminds, and provides opportunities for implementing new or improved procedures. Establish a system to highlight when employees are due for retraining, retesting, or recertification.

Feedback, compliance verification, and measurement

Motivate and provide the mechanism for program improvement. Sharing yield or productivity, quality, and reliability data with employees demonstrates the effectiveness of the program and of their efforts. Tracking these same numbers can indicate that it’s time for retraining or whether modifications are required in the training program.

Design and delivery of an effective ESD training program can be just as important as the procedures and materials used in your ESD control program. Without an effective personnel training program, investments in ESD materials can be wasted. A training program that is built on identifiable and measurable performance goals helps assure employee understanding, implementation and success.

A key method of training effectiveness is observation of the operator in the EPA following ESD control procedures and precautions. Non-compliance with required ESD control program practices should be treated in the same manner of other impermissible actions that are handled through the company’s disciplinary process. This includes verbal warnings, re-training, written warnings, and eventually re-assignment or termination.

Compliance Verification Auditing

Developing and implementing an ESD control program itself is obvious. What might not be so obvious is the need to continually review, verify, analyze, feedback and improve. You will be asked to continually identify the program’s financial return on investment and to justify expenditures with the cost savings realized. Technological changes will dictate improvements and modifications. Feedback to employees and top management is essential. Management commitment will need continuous reinforcement.

Like training, regular program compliance verification and auditing becomes a key factor in the successful management of ESD control programs. The mere presence of the auditing process spurs compliance with program procedures. It helps strengthen management’s commitment. Program compliance verification reports should trigger required corrective action and help foster continuous improvement.

The benefits to be gained from regular compliance verification of ESD control procedures are numerous.

• Prevent problems before they occur rather than always fighting fires.
• Identify problems and take corrective action.
• Identify areas in which our programs may be weak and provide us with information required for continuous improvement.
• Leverage limited resources effectively.
• Determine when our employees need to be retrained.
• Improve yields, productivity, and reliability.
• Bind our ESD program together into a successful effort.

An ESD control program compliance verification audit measures performance to the ESD Control Program Plan’s required limits. Typically, we think of the ESD program compliance verification as a periodic review and inspection of the ESD protective area (EPA) verifying the correct use of packaging materials, wearing of wrist straps, following defined procedures, and similar items. Auditing can range from informal surveys of the processes and facilities to the more formal third-party audits for ISO 9000 or ANSI/ESD S20.20 certification.

Requirements for Effective Compliance Verification

Regardless of the structure, effective compliance verification revolves around several factors. First, the existence of a written and well-defined ESD Control Program Plan with defined required limits for each EPA ESD control item. It is difficult to measure performance if you do not have anything to measure against. Yet, you quite frequently hear an auditor ask, “Some people say you should measure less than 500 volts in an EPA, but others say you should measure less than 100 volts. What’s acceptable when I audit the factory floor?” Obviously, this question indicates a lack of a formal ESD Control Program Plan defined required limits and test procedures, and the audit will be relatively ineffective.

Second, the taking of some measurements – typically measuring resistance and detecting the presence of charge or fields. Therefore, you will need test equipment to conduct EPA compliance verification. As a minimum, you will need an electrostatic field meter, a high range resistance meter, a ground AC outlet tester, and appropriate electrodes and accessories.

Third, include all areas in which ESD control is required to protect electrostatic discharge sensitive (ESDS) items. Typically included are receiving, inspection, stores and warehouses, assembly, test and inspection, research and development, packaging, field service repair, offices and laboratories, and cleanrooms. All of the areas listed in the ESD Control Program Plan are subject to compliance verification. Even the areas that are excluded from the plan need to be reviewed to ensure that unprotected ESDS devices are not handled in those areas. In the event that devices do enter those areas (e.g. Engineering and Design), mechanisms must be put in place to ensure that the devices are handled as non-conforming product.

Similarly, we need to audit all of the various processes, materials, and procedures that are used in our ESD control programs – personnel, equipment, wrist straps, floors, clothing, worksurfaces, continuous monitors, seating, training, and grounding. Fourth, we need to conduct compliance verification audits frequently and regularly. However, the user must determine the frequency (and if sampling is appropriate). Per Compliance Verification ESD TR53 ANNEX A Test Frequency “The objective of the periodic test procedures listed in this document is to identify if significant changes in ESD equipment and materials performance have occurred over time. Test frequency limits are not listed in this document, as each user will need to develop their own set of test frequencies based on the critical nature of those ESD sensitive items handled and the risk of failure for the ESD protective equipment and materials.

Examples of how test frequencies are considered: Daily wrist strap checks are sufficient in some applications, where in other operations constant wrist strap monitoring may be used for added operator grounding reliability. Packaging checks may depend on the composition of the packaging and its use. Some packaging may have static control properties that deteriorate more quickly with time and use and some packaging may be humidity dependent and may have limited shelf life. Some materials, such as ESD floor finishes, may require more frequent monitoring because of their lack of permanency. Other materials, such as ESD vinyl floor covering, may require less monitoring.

The testing of a floor should also be considered after maintenance on the floor has been performed.” The actual frequency of compliance verification audits depends upon your facility and the ESD problems that you have. Following an ESD Control Program initial audit, some experts recommend auditing each department once a month if possible and probably a minimum of six times per year. If this seems like a high frequency level, remember that these regular verification audits are based upon a sampling of work areas in each department, not necessarily every workstation. Once you have gotten your program underway, your frequency of audit will be based on your experience. If your audits regularly show acceptable levels of conformance and performance, you can reduce the frequency and the sampling.

If, on the other hand, your audits regularly uncover continuing problems, you will want to increase the frequency and the sampling. Fifth, we need to maintain trend charts and detailed records and prepare reports. They help assure that specified procedures are followed on a regular basis. The records are essential for quality control purposes, corrective action and compliance with ISO-9000. Finally, upon completion of the compliance verification audit, it is essential to implement corrective action if deficiencies are discovered. Trends need to be tracked and analyzed to help establish corrective action, which may include retraining of personnel, revision of requirement documents or processes, or modification of the existing facility.

Types of Audits

There are three types of ESD audits: program management audits, quality process checking, and ESD Control Program compliance verification (work place) audits. Each type is distinctively different and each is vitally important to the success of the ESD program.

Program management audits measure how well a program is managed and the strength of the management commitment. The program management audit emphasizes factors such as the existence of an effective implementation plan, realistic program requirements, ESD training programs, regular compliance verification audits, and other critical factors of program management. The program management audit typically is conducted by a survey specifically tailored to the factors being reviewed. Because it’s a survey, the audit could be conducted without actually visiting the site. The results of this audit indirectly measure work place compliance and are particularly effective as a means of self-assessment for small companies as well as large global corporations.

Quality process checking applies statistical quality control techniques to the ESD process and is performed by operations personnel. This is not a periodic verification audit, but rather tracking daily effectiveness of the program. Visual and electrical checks of the procedures and materials, wrist strap testing for example, are used to monitor the quality of the ESD control process. Checking is done on a daily, weekly or monthly basis. Trend charts and detailed records trigger process adjustments and corrective action. They help assure that specified procedures are followed on a regular basis. The records are essential for quality control purposes, corrective action and compliance with ISO-9000.

ESD Control Program Compliance Verification audits verify that program procedures are followed and that ESD control materials and equipment are within required limits or are functioning properly. Compliance Verification audits are performed on a regular basis, often monthly, and utilize sampling techniques and statistical analysis of the results. The use of detailed checklists and a single auditor assures that all items are covered and that the audits are performed consistently over time.

Basic Auditing Instrumentation

Special test equipment will be required to conduct EPA compliance verification. The specific test equipment will depend on what you are trying to measure, the precision you require and the sophistication of your static control and material evaluation program. However, as a minimum, you will need an electrostatic field meter, a high range resistance meter, a ground/AC outlet tester, and appropriate electrodes and accessories. Additional test equipment might include a charged plate monitor, footwear and wrist strap testers, chart recorders/data acquisition systems and timing devices, discharge simulators, and ESD event detectors. Although this equipment must be accurate and calibrated according to the vendor’s recommendations, it needs not be as sophisticated as laboratory instruments. The compliance verification audit is intended to verify basic functions and not for product qualification of ESD control equipment or materials. The compliance verification audit is intended to verify basic functions and not as a product qualification of ESD control items or materials. You want the right tool for the job. Just as you would not buy a hammer if you are were planning to saw wood, you would not purchase an electrometer to measure static voltages on a production line. Remember, many of the test equipment you might choose for compliance verification are good indicators, but not suitable for precise evaluation of materials. However, be sure that you can correlate the measurements obtained on the factory floor with those obtained in the laboratory. If you are making measurements according to specific standards or test methods, be sure the instrumentation meets the requirements of those documents.

With a hand-held electrostatic field meter, you can measure the presence of electrostatic fields in your environment allowing you to identify problems and monitor your ESD control program. These instruments measure the electrostatic field associated with a charged object. Many electrostatic field meters simply measure the gross level of the electrostatic field and should be used as general indicators of the presence of a charge and the approximate level of electrical potential of the charge. Others will provide more precise measurement for material evaluation and comparison.

For greater precision in facility measurements or for laboratory evaluation, a charged plate monitor is a useful instrument that can be used in many different ways; for example to evaluate the performance of flooring materials or measuring the offset voltage (balance) and discharge times of ionizers.

Because grounding is so important, resistance is one of the key factors in evaluating ESD control materials. A high range resistance meter becomes a crucial instrument. Most resistance measurements are made using a 100 volt or 10 volt test voltage. The resistance meter you choose should be capable of applying these voltages to the materials being tested. In addition, the meter should be capable of measuring resistance ranges of 10³ to 10¹² ohms. With the proper electrodes and cables, you will be able to measure the resistance of flooring materials, worksurfaces, equipment, furniture, garments, and some packaging materials.

The final instrument is a ground/AC outlet tester. With this device you can measure the continuity of your ESD grounds, check the impedance of the equipment grounding conductor (3^rd wire AC ground) as well as verify that the wiring of power outlets in the EPA is correct.

Areas, Processes, and Materials to be Audited

Previously we stated that ESD protection was required “wherever unprotected ESD sensitive devices are handled.” Obviously, our audits need to include these same areas. Table 1 indicates some of the physical areas that may be part of the ESD Control Program Plan and therefore will be involved in Compliance Verification Audits. Remember, some areas may be excluded from the Plan depending on the Scope of the Plan.

As noted in Part 3 Table 1 Typical Facility Areas Requiring ESD Protection

Similarly, we need to conduct Compliance Verification audits of all the various requirements that are used in our ESD Control Program Plan. Some of these are shown in Table 2.

Checklists

Checklists can be helpful tools for conducting Compliance Verification audits. However, it is important that ESD control program requirements are well documented and accessible to avoid a tendency for checklists becoming de facto lists of requirements. Table 3 indicates the type of questions and information that might be included in an auditing checklist. Other checklists are in the ESD Handbook ESD TR20.20 section 4.3.3. Your own checklists, of course, will be based on your specific needs and program requirements. They should conform to your actual ESD control procedures and specifications and they should be consistent with any ISO 9000 requirements you may have. For ANSI/ESD S20.20 based ESD Control Programs, the recognized Certification Bodies (Registrars) use a formal checklist supplied by the ESD Association to aid in conducting the Certification Audit.

In addition to checklists, you will use various forms for recording the measurements you make: resistance, voltage generation, etc. Part of your compliance verification audit will also include the daily logs used on the factory floor such as those used for wrist strap checking.

Reporting and Corrective Action

Upon completion of the compliance verification auditing process, Reports should be prepared and distributed in a timely manner. Details of the audits need to be fully documented for ISO-9000 or ANSI/ESD S20.20 certification. As with all audits, it is essential to implement corrective action if deficiencies are discovered. Trends need to be tracked and analyzed to help establish corrective action, which may include retraining of personnel, revision of requirement documents or processes, or modification of the existing facility.

Conclusion

Compliance verification and personnel ESD control training are key ANSI/ESD S20.20 and IEC 61340-5-1 requirements to maintain an effective ESD control program. They help assure that ESDS handling procedures are properly implemented and can provide a management tool to gauge program effectiveness and to make continuous improvement.

For Further Reference

• ANSI/ESD 20.20—Electrostatic Discharge Control Program, ESD Association, Rome, NY
• ESD TR20.20-2001, ESD Control Handbook , ESD Association, Rome, NY.
• “An Effective ESD Awareness Training Program,” Owen J. McAteer, EOS/ESD Symposium Proceedings, 1980, ESD Association, Rome, NY.
• “Facility Evaluation: Isolating Environmental ESD Issues,” Stephen A. Halperin, EOS/ESD Symposium Proceedings, 1980, ESD Association, Rome, NY.
• “The Production Operator: Weak Link or Warrior in the ESD Battle?” G. E. Hansel, EOS/ESD Symposium Proceedings, 1983,ESD Association, Rome, NY
• “A Realistic and Systematic ESD Control Plan,” G. T. Dangelmayer, EOS/ESD Symposium Proceedings, 1984, ESD Association, Rome, NY.
•   “Employee Training for Successful ESD Control,” G. T. Dangelmayer, E. S. Jesby, EOS/ESD Symposium Proceedings, 1985, ESD Association, Rome, NY
• “A Tailorable ESD Control Program for the Manufacturing Environment,” Norman B. Fuqua, EOS/ESD Symposium Proceedings, 1986, ESD Association, Rome, NY.
• “Internal Quality Auditing and ESD Control,” D. H. Smith, C.D. Rier, EOS/ESD Symposium Proceedings, 1986, ESD Association, Rome, NY
• “Developing and Maintaining an Effective ESD Training Program,” F. Dinger, EOS/ESD Symposium Proceedings, 1988, ESD Association, Rome, NY
• “Standardized Qualification and Verification Procedures for Electrostatic Discharge (ESD) Protective Materials,” Adrienne R. Kudlich, et al, EOS/ESD Symposium Proceedings, 1988, ESD Association, Rome, NY.
• “Modular ESD Certification Training Program,” M. Berkowitz, B. Hamel, EOS/ESD Symposium Proceedings, 1989, ESD Association, Rome, NY
• “Tracking Results of an ESD Control Program Within a Telecommunications Service Company,” R. J. Zezulka, EOS/ESD Symposium Proceedings, 1989, ESD Association, Rome, NY
• “Development of a Corporate Standardization Program for ESD Control Materials and Products at Hughes Aircraft Company and Delco Electronics,” J. L. Joyce, R. L. Johnson, EOS/ESD Symposium Proceedings, 1991, ESD Association, Rome, NY.
• “Implementation of Computer-Based ESD Training: A Case Study Comparing the Computer Approach with Traditional Classroom Techniques,” J. Woodward-Jack, H. Sommerfeld, EOS/ESD Symposium Proceedings, 1991, ESD Association, Rome, NY
• “A Systematic ESD Program Revisited,” G. T. Dangelmayer, EOS/ESD Symposium Proceedings, 1992, ESD Association, Rome, NY
• “You’ve Implemented An ESD Program –­ What’s Next?” W. Y. McFarland, R. A. Brin, EOS/ESD Symposium Proceedings, 1993, >ESD Association, Rome, NY
• “A Successful ESD Training Program,” L. Snow, G. T. Dangelmayer, EOS/ESD Symposium Proceedings, 1994, ESD Association, Rome, NY
• “Implementing an ESD Program in a Multi-National Company: A Cross-Cultural Experience,” W. H. Tan, EOS/ESD Symposium Proceedings, 1994, ESD Association, Rome, NY
•  “Effectiveness of ESD Training Using Multimedia,” G. Smalanskas, J. Mason, EOS/ESD Symposium Proceedings, 1995,ESD Association, Rome, NY
•  “ESD Demonstrations to Increase Engineering and Manufacturing Awareness,” G. Baumgartner, EOS/ESD Symposium Proceedings, 1996, ESD Association, Rome, NY
• “ESD Program Auditing: The Auditor’s Perspective,” T.L. Theis, et al, EOS/ESD Symposium Proceedings, 1997, ESD Association, Rome, NY
• “Procedures For The Design, Analysis and Auditing of Static Control Flooring/Footwear Systems”, L. Fromm, et al, EOS/ESD Symposium Proceedings, 1997, ESD Association, Rome, NY
• “Continuous Voltage Monitoring Techniques for Improved ESD Auditing,” A. Wallash, EOS/ESD Symposium Proceedings, 2003, ESD Association, Rome, NY
• “A Comparison of High-Frequency Voltage, Current and Field Probes and Implications for ESD/EOS/EMI Auditing”, A. Wallash, V. Kraz, EOS/ESD Symposium Proceedings, 2007, ESD Association, Rome, NY
• IEC 61340-5-1, ed. 1.0, “Electrostatics – Part 5.1: Protection of electronic devices from electrostatic phenomena – General requirements”, IEC, Geneva, Switzerland, 2007-08.

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Fundamentals of Electrostatic Discharge
Part Two – Principles of ESD Control – ESD Control Program Development
© 2013, EOS/ESD Association, Inc., Rome, NY

In Part One of this series, Introduction to ESD, we discussed the basics of electrostatic charge and discharge, the mechanisms of creating charge, materials, types of ESD damage, ESD events, and ESD sensitivity. We concluded our discussion with the following summary:

1. Virtually all materials, including conductors, can be triboelectrically charged.
2. The amount of charge is affected by material type, speed of contact and separation, humidity, and several other factors.
3. Charged objects have electrostatic fields.
4. Electrostatic discharge can damage devices so a parameter fails immediately, or ESD damage may be a latent defect that may escape mediate detection, but may cause the device to fail prematurely.
5. Electrostatic discharge can occur throughout the manufacturing, test, shipping, handling, or operational processes, and during field service operations.
6. ESD damage can occur as the result of a discharge to the device, from the device, or from charge transfers resulting from electrostatic fields. Devices vary significantly in their sensitivity or susceptibility to ESD.

Protecting products from the effects of ESD damage begins by understanding these key concepts of electrostatic charges and discharges. An effective ESD control program requires an effective training program where all personnel involved understand the key concepts. Armed with this information, you can then begin to develop an effective ESD control program. In Part Two we will focus on some basic principles of ESD control and ESD control program development.
Basic Principles of Static Control

Controlling electrostatic discharge (ESD) in the electronics manufacturing environment is a formidable challenge. However, the task of designing and implementing ESD control programs becomes less complex if we focus on just six basic principles of static control. In doing so, we also need to keep in mind the ESD corollary to Murphy’s law, “no matter what we do, static charge will try to find a way to discharge.”

1. Design In Protection

The first principle is to design products and assemblies to be as resistant as reasonable from the effects of ESD. This involves such steps as using less static sensitive devices or providing appropriate input protection on devices, boards, assemblies, and equipment. For engineers and designers, the paradox is that advancing product technology requires smaller and more complex geometries that often are more susceptible to ESD. The Industry Council on ESD Target Levels and the ESD Association’s “Electrostatic Discharge (ESD) Technology Roadmap”, revised April 2010, suggest that designers will have less ability to provide the protection levels that were available in the past. Consequently, the ESD target levels are reduced to 1000 volts for Human Body Model robustness and 250 volts for robustness against the Charged Device Model, with tendency to reduce these values further. Those target values are considered to be realistic and safe levels for manufacturing and handling of today’s products using basic ESD control methods as described in international industry standards as e.g. ANSI/ESD S20.20 or IEC 61340-5-1. When devices with lower ESD target levels must be used and handled, application-specific controls beyond the principles described here may be required.

2. Define the Level of Control Needed in Your Environment.

What is the most sensitive or ESD susceptible ESDS you are using and what is the classification of withstand voltage of the products that you are manufacturing and shipping? In order to get an idea of what is required, it is best to know the Human-Body Model (HBM) and Charged-Device Model (CDM) sensitivity levels for all devices that will be handled in the manufacturing environment. ANSI/ESD S20.20 and IEC 61350-5-1, both published in 2007,  define control program requirements for items that are sensitive to 100 volts HBM; future version of those standards will most likely address also items that are sensitive to 200 volts CDM.  With documentation, both standards allows requirements to be tailored as appropriate for specific situations.

3.  Identify and Define the Electrostatic Protected Areas (EPA).

Per Glossary ESD ADV1.0 an ESD protected area is “A defined location with the necessary materials, tools and equipment capable of controlling static electricity to a level that minimizes damage to ESD susceptible items”. These are the areas in which you will be handling ESD sensitive items and the areas in which you will need to implement the basic ESD control procedures including bonding or electrically connecting all conductive and dissipative materials, including personnel, to a known common ground.

4.  Reduce Electrostatic Charge Generation

If projections of ESD sensitivity are correct, ESD protection measures in product design will be increasingly less effective in minimizing ESD losses. The fourth principle of control is to reduce electrostatic charge generation and accumulation in the first place. It’s fairly basic: no charge – no discharge. We begin by eliminating as many static charge generating processes or materials, specifically high-charging insulators such as common plastics, as possible from the EPA work environment. We keep conductive/dissipative materials at the same electrostatic potential using equipotential bonding or attaching to equipment ground. Electrostatic discharge does not occur between materials kept at the same potential. In the EPA, ESD control items should be used in place of more common factory products such as worksurface mats, flooring, smocks, etc. which are to be attached to ground to reduce charge generation and accumulation. Personnel are grounded via wrist straps or a flooring/footwear system. While the basic principle of “controlling static electricity to a level that minimizes damage” should be followed, complete removal of charge generation is not achievable.

5.  Dissipate and Neutralize

Because we simply can’t eliminate all generation of electrostatic charge in the EPA, our fifth principle is to safely dissipate or neutralize those electrostatic charges that do occur. Proper grounding and the use of conductive or dissipative materials play major roles. For example, personnel starting work may have a charge on their body; they can have that charge removed by attachment to a wrist strap or when they step on ESD flooring while wearing ESD control footwear. The charge goes to ground rather than being discharged into a sensitive part. To prevent damaging a charged device, the magnitude of the discharge current can be controlled with static dissipative materials.

For some objects, such as common plastics and other insulators, being non-conductors grounding cannot remove an electrostatic charge because there is no pathway which is conductive enough to reduce the charge in a reasonable time. If the object cannot be eliminated from the EPA, ionization can be used to neutralize charges on these insulators. The ionization process generates negative and positive ions. The like charged ions are repelled from a charged object while the opposite charged ions are attracted to the surface of a charged object, therefore neutralizing the object (see Figure 1). If the ionizer is balanced, the net charge is zero.

6. Protect Products

Our final ESD control principle is to prevent discharges that do occur from reaching susceptible parts and assemblies. There are a variety of ESD control packaging and material handling products to use both inside and outside the EPA. One way is to protect ESD sensitive products and assemblies with proper grounding or shunting that will “dissipate” any discharge away from the product. A second method is to package, to store, or to transport ESD sensitive products in packaging that is low charging and are conductive/dissipative so can remove charges when grounded. In addition to these properties, packaging used to move ESD sensitive items outside the EPA should have the ESD control property of “discharge shielding”. These materials should effectively shield the product from charges and discharges, as well as reduce the generation of charge caused by any movement of product within the container.

Elements of an Effective ESD Control Program

While these six principles may seem rather basic, they can guide us in the selection of appropriate materials and procedures to use in effectively controlling ESD. In most circumstances, effective programs will involve all of these principles. No single procedure or product will do the whole job; rather effective static control requires a full ESD control program.

How to we develop and maintain a program that puts these basic principles into practice? How do we start? What is the process? What do we do first? Ask a dozen experts and you may get a dozen different answers. But, if you dig a little deeper, you will find that most of the answers center on similar key elements. You will also find that starting and maintaining an ESD control program is similar to many other business activities and projects. Although each company is unique in terms of its ESD control needs, there are at least 6 critical elements to successfully developing, implementing, and maintaining an effective ESD control program (see Figure 2).

1.  Establish an ESD Coordinator and ESD Teams

A team approach particularly applies to ESD because the problems and the solutions cross various functions, departments, divisions and suppliers in most companies. ESD team composition includes line employees as well as department heads or other management personnel. The ESD team may also cut across functions such as incoming inspection, quality, training, automation, packaging, and test. ESD teams or committees help assure a variety of viewpoints, the availability of the needed expertise, and commitment to success. An active ESD team helps unify the ongoing effort.

Heading this ESD team effort is an ESD program coordinator (“ESD coordinator”). Ideally, this responsibility should be a full-time job. However, we seldom operate in an ideal environment and you may have to settle for the function to be a major responsibility of an individual. The ESD coordinator is responsible for developing, budgeting, and administering the program. The ESD coordinator also serves as the company’s internal ESD consultant to all ESD control programs areas.

2.  Assess Your Organization, Facility, Processes and Losses

Your next step is to gain a thorough understanding of your environment and its impact on ESD. Armed with your product quality loss and ESD sensitivity data, you can evaluate your facility, looking for areas and procedures that may possibly cause ESD problems. Be on the lookout for things such as static generating materials, personnel handling procedures for ESD sensitive items, and contacts of ESD sensitive devices to conductors

Document your processes or work instructions. Observe the movement of people and materials through the areas. Note those areas that would appear to have the greatest potential for ESD problems. Remember, that ESD can occur in the warehouse just as it can in the assembly areas. Then conduct a thorough facility survey or audit. Measure personnel, equipment, and materials to identify proper resistance ranges and the presence of electrostatic fields in your environment.

Before seeking solutions to your problems, you will need to determine the extent of your product quality losses to ESD. These losses may be reflected in receiving reports, Quality Assurance and Quality Control records, customer returns, in-plant yields, failure analysis reports, and other data that you may already have or that you need to gather. This information not only identifies the magnitude of the problem, but also helps to pinpoint and prioritize areas that need attention. Where available, the potential for future problems as a result of technology roadmaps and internal product evolution should be considered.

Document your actual and potential ESD losses in terms of defective components, rework, customer returns, and failures during final test and inspection. Use data from outside sources or the results of your pilot program for additional support. Develop estimates of the savings to be realized from implementing an ESD control program.

You will also want to identify those items (components, assemblies, and finished products) that are the most sensitive to ESD noting the classification or withstand voltage. Note that two functionally identical items from two different suppliers may not have similar ESD ratings.

3.   Establish and Document Your ESD Control Program Plan

After completing your assessment, you can begin to develop and document your ESD control program plan. The plan should cover the scope of the program and include the tasks, activities and procedures necessary to protect the ESD sensitive items at or above the ESD sensitivity level chosen for the plan. Prepare and distribute written procedures and specifications so that all departments have a clear understanding of what is to be done. Fully documented procedures will help you meet the administrative and technical elements of ANSI/ESD S20.20 or IEC 61340-5-1 and help you with ISO 9000 certification as well

4.   Build Justification to Get the Top Management Support

To be successful, an ESD program requires the support of your top management, at the highest level possible. What level of commitment is required? To obtain commitment, you will need to build justification for the plan. You will need to emphasize quality and reliability, the costs of ESD damage, the impact of ESD on customer service and product performance. It may be useful to conduct a pilot program if the experience of other companies is not sufficient and you have an expectation that you can show meaningful results in the pilot.

Prepare a short corporate policy statement on ESD control. Have top management co-sign it with the ESD coordinator. Periodically, reaffirm the policy statement and management’s commitment to it. Published articles such as The “Real” Cost of ESD Damage by Terry Welsher should be provided to top management.

5. Develop and Implement a Training Plan

Train and retrain your personnel in ESD control and your company’s ESD control program and procedures. Training should include testing or other method to verify comprehension. Proper training for line personnel is especially important. They are often the ones who have to live with the procedures on a day-to-day basis. A sustained commitment and mindset among all employees that ESD prevention is a valuable, on-going effort by everyone is one of the primary goals of training. Please be aware that it might be necessary to tailor the ESD training to the education of the trainees.

ANSI/ESD S20.20 requires a written training plan, however, your company has the flexibility to determine how best to design the plan.

6. Develop and Implement a Compliance Verification Plan

Developing and implementing the program itself is obvious. What might not be so obvious is the need to continually review, audit, analyze, obtain feedback and improve. Auditing is essential to ensure that the ESD control program is successful. You will be asked to continually identify the return on investment of the program and to justify the savings realized. Technological changes will dictate improvements and modifications. Feedback to employees and top management is essential. Management commitment will need reinforcement.

Include both reporting and feedback to management, the ESD team, and other employees as part of your plan. Management will want to know that their investment in time and money is yielding a return in terms of quality, reliability and profits. ESD team members need a pat on the back for a job well done. Other employees will want to know that the procedures you have asked them to follow are indeed worthwhile. It is helpful to integrate the process improvement process into the overall quality system and use the existing quality tools such as root cause analysis and corrective action reports. As you find areas that need work, be sure to make the necessary adjustments to keep the program on track.

Conduct periodic evaluations of your program and audits of your facility. You will find out if your program is successful and is giving you the expected return. You will spot weaknesses in the program and shore them up. You will discover whether the procedures are being followed.

ANSI/ESD S20.20 and IEC 61340-5-1 require a written compliance verification plan, however, your company has the flexibility to determine how best to design the plan. Test procedures are described in ESD TR53-01-06 Compliance Verification of ESD Protective Equipment and Materials which is available as complimentary download from www.ESDA.org. The objective is to identify if significant changes in ESD equipment and materials performance have occurred over time. Each user will need to develop their own set of test frequencies based on the critical nature of those ESD sensitive items handled and the risk of failure for the ESD protective equipment and materials.

Conclusion

Six principles of ESD control and six key elements to ESD control program development and implementation are your guideposts for effective ESD control programs.

The six basic principles of static control are:

1. Design in protection
2. Define the level of control needed in your environment
3. Identify and define the electrostatic protected areas (EPA)
4. Reduce electrostatic charge generation
5. Dissipate and neutralize
6. Protect products

Six key elements to to ESD control program development and implementation are:

1. Establish an ESD Coordinator and ESD teams
2. Assess your organization, facility, processes and losses
3. Establish and document your ESD control program plan
4. Build justification to get the top management support
5. Develop and implement a training plan
6. Develop and implement a compliance verification plan

In Part Three, we’ll take a close look at specific procedures and materials that become part of your ESD control program.

For Additional Information

• ANSI/ESD S20.20-2007 – Standard for the Development of Electrostatic Discharge Control Program, ESD Association, Rome, NY.
• Dangelmayer, Theodore, ESD Program Management: A Realistic Approach to Continuous, Measurable Improvement in Static Control, 1999, Kluwer Academic Publishers, Boston, MA
• ESD TR20.20, ESD Control Handbook, ESD Association, Rome, NY.
• ESD TR53-01-06, Compliance Verification of ESD Protective Equipment and Materials, ESD Association, Rome, NY.
• Industry Council on ESD Target Levels, White Paper I: “A Case for Lowering Component Level HBM/MM ESD Specifications and Requirements”, Revision 2.0, October 2010.
• Industry Council on ESD Target Levels, White Paper II: “A Case for Lowering Component
• Level CDM ESD Specifications and Requirements”, Revision 2.0, April 2010.
• ESDA Technology Roadmap,  March 2013
• IEC 61340-5-1, ed. 1.0, “Electrostatics – Part 5.1: Protection of electronic devices from electrostatic phenomena – General requirements”, IEC, Geneva, Switzerland, 2007-08.
• Terry Welsher, The “Real” Cost of ESD Damage, InCompliance, May 01, 2010.

Figure 1: Prinziple of neutralization of a charged object by an ionizer that generates negative and positive ions. The like charged ions are repelled from a charged object while the opposite charged ions are attracted to the surface of a charged object, neutralizing the object

Figure 2: Six critical elements of a successful ESD control program