Fundamentals of Electrostatic Discharge – Part Two: Principles of ESD Control – ESD Control Program Development

Published in InCompliance Magazine
Written by The ESD Association
April 01, 2014

The ESD Association has published the second of a six part article titled Fundamentals of Electrostatic Discharge in the April edition of InCompliance. Part two covers the following topics:

  • Basic Principles of Static Control
  • Design In Protection
  • Define the Level of Control Needed in Your Environment
  • Identify and Define the Electrostatic Protected Areas (EPA)
  • Reduce Electrostatic Charge Generation
  • Dissipate and Neutralize
  • Protect Products
  • Elements of an Effective ESD Control Program
  • Establish an ESD Coordinator and ESD Teams
  • Assess Your Organization, Facility, Processes and Losses
  • Establish and Document Your ESD Control Program Plan
  • Build Justification to Get the Top Management Support
  • Develop and Implement a Training Plan
  • Develop and Implement a Compliance Verification Plan

The Read the rest of Fundamentals of Electrostatic Discharge – Part Two: Principles of ESD Control – ESD Control Program Development HERE.

Desco offers a no-charge ESD surveys as a way to have an extra set of eyes evaluate your factory’s ESD control environments. Our sales reps are outfitted with equipment to perform ESD Surveys. Using the ESD Association’s standards and their equipment, Desco sales reps will take measurements, make observations, and provide you with a written report to help you manage your program. If you are interested in an ESD Survey and/or a test equipment demo please contact us HERE.

Receive a Free Wrist Strap Kit with Each Multi-Mount Monitor (Item #19228) Purchased

19228 Single-Wire Continuous Monitor

To claim your free wrist straps, submit your information and a copy of your invoice for your previously purchased 19228.  Select one wrist strap kit from the items listed below for each 19228 purchased.  This offer is only available for purchases of 19228 made after 2014-03-03. 
 
Submit your invoice here.
Wrist Strap Kits

Adjustable Elastic Wrist Strap Kit with 6′ Coil Cord

Sapphire Jewel® Adjustable Wrist Strap Kit with 6′ Coil Cord

09070 - Adjustable Elastic Wrist Strap
09100 - Jewek® Adjustable Elastic Wrist Strap Kit

Jewel® MagSnap Adjustable Wrist Strap Kit with 6′ Coil Cord

Jewel® MagSnap Adjustable Wrist Strap Kit with 6′ Coil Cord and Right Angle Banana

09184 - Jewel® MagSnap Adjustable Elastic Wrist Strap
09202 - Jewel® MagSnap Adjustable Elastic Wrist Strap

You’re Invited – ESD Seminars in Tuscon, Arizona

The EOS/ESD Association is  excited to offer two ESD Seminars at the The Westin La Paloma Resort, Tucson, Arizona in April

March 31-April 1, 2014
ESD Device Design Essentials
Instructors: Gianluca Boselli and Michael G. Khazhinsky

This Seminar provides a broad exposure to the essentials of design sensitivity trends that affect ESD control practices. It offers a two-day comprehensive set of the fundamentals of ESD testing, high-current physics, and ESD modeling principles which are applied to ESD Protection Design. Special ESD design cases are explored and EOS/ESD failure models and mechanisms are discussed. The seminar provides practical examples for troubleshooting of on-chip ESD failures.

Cost: $1,510 Members, $1,610 Non-members

April 7-8, 2014
Essentials for ESD Programs
Factory: Technologies * Controls * Procedures
Instructors: Carl Newberg and Dr. Terry L. Welsher

This Seminar is a broad exposure to the essentials of ESD programs. It offers a two-day comprehensive set of factory technologies and procedures designed for managers, technicians, and specialists desiring ESD control program training and information. Key concepts of ESDA tutorials on factory technologies, controls, and procedures that provide a comprehensive overview of factory processes.

 Cost: $1,510 Members, $1,610 Non-members

Register Here

Fundamentals of Electrostatic Discharge – Part One: An Introduction to ESD

Published in InCompliance Magazine
Written by The ESD Association
January 01, 2014

The ESD Association has published the first of a six part article titled Fundamentals of Electrostatic Discharge in the January edition of InCompliance. The article starts with the following introduction:

To many people, Electrostatic Discharge (ESD) is only experienced as a shock when touching a metal doorknob after walking across a carpeted floor or after sliding across a car seat. However, static electricity and ESD has been a serious industrial problem for centuries. As early as the 1400s, European and Caribbean military forts were using static control procedures and devices trying to prevent inadvertent electrostatic discharge ignition of gunpowder stores.

By the 1860s, paper mills throughout the U.S. employed basic grounding, flame ionization techniques, and steam drums to dissipate static electricity from the paper web as it traveled through the drying process. Every imaginable business and industrial process has issues with electrostatic charge and discharge at one time or another. Munitions and explosives, petrochemical, pharmaceutical, agriculture, printing and graphic arts, textiles, painting, and plastics are just some of the industries where control of static electricity has significant importance. The age of electronics brought with it new problems associated with static electricity and electrostatic discharge. And, as electronic devices become faster and the circuitry getting smaller, their sensitivity to ESD in general increases. This trend may be accelerating. The ESD Association’s “Electrostatic Discharge (ESD) Technology Roadmap”, revised April 2010, includes “With devices becoming more sensitive through 2010-2015 and beyond, it is imperative that companies begin to scrutinize the ESD capabilities of their handling processes”. Today, ESD impacts productivity and product reliability in virtually every aspect of the global electronics environment.

Despite a great deal of effort during the past thirty years, ESD still affects production yields, manufacturing cost, product quality, product reliability, and profitability. The cost of damaged devices themselves ranges from only a few cents for a simple diode to thousands of dollars for complex integrated circuits. When associated costs of repair and rework, shipping, labor, and overhead are included, clearly the opportunities exist for significant improvements. Nearly all of the thousands of companies involved in electronics manufacturing today pay attention to the basic, industry accepted elements of static control. ESD Association industry standards are available today to guide manufacturers in establishing the fundamental static charge mitigation and control techniques (see Part Six – ESD Standards). It is unlikely that any company which ignores static control will be able to successfully manufacture and deliver undamaged electronic parts.

Read the rest of Fundamentals of Electrostatic Discharge – Part One: An Introduction to ESD HERE.

Desco offers a no-charge ESD surveys as a way to have an extra set of eyes evaluate your factory’s ESD control environments. Our sales reps are outfitted with equipment to perform ESD Surveys. Using the ESD Association’s standards and their equipment, Desco sales reps will take measurements, make observations, and provide you with a written report to help you manage your program. If you are interested in an ESD Survey and/or a test equipment demo please contact us HERE.

You’re invited to the ESD Association Korea Chapter Regional Tutorials

ESD Basics for the Program Manager

Cleanroom Considerations for the Program Manager

Ionization Issues and Answers for the Program Manager

March 11-12, 2014

Conference Center, COEX, 159, Samseong 1(il)-dong, Gangnam-gu, Seoul, South Korea

Make sure you have people with the right knowledge to maintain your ESD control program at the highest level.

Learn from top industry professionals.

ESDA Certification courses are part of the globally recognized Certified Professional Program Manager Program developed by the ESD Association.

Conference Center, COEX,
159, Samseong 1(il)-dong, Gangnam-gu,
Seoul, South Korea

Register Here

Ionization and Ions

Ionization is probably the most misunderstood and under used technology for controlling ESD. There are some cases where ionization would be primary method of controlling ESD in an ESD Protected Area and there are others where it would not even be necessary. The need for ionization largely depends on what and how ESD susceptible devices are being handled.

In a lasted issue InCompliance, the late Niels Jonassen’s “Mr Static” column discusses the nature of Ions, their behavior, and how ionization works. He notes:

If the charged insulator is exposed to an atmosphere containing ions of polarity opposite that of the charge, the field will attract ions, which will move toward the body and neutralize the charge. At least that’s what appears to happen.

But a more strict formulation would be that the original (excess) charge is still there, and so is its field. The oppositely charged ions, attracted from the air, will deposit around the original charge, but not annihilate it. The resulting field, the sum of the fields from the opposite charges, will be zero, or at least very close to zero.

The use of air ionization for abating static electric effects is a slow method, compared to methods like the grounding of conductors or surface treatment with topical antistats. But it should be stressed that when we are talking about charged insulators, exposure to ionized air is the only method to remove the effects of the charge.

Read the rest of Niels Jonassen’s “Ions” article HERE

The primary function of ionization in an ESD Protected Area is to neutralize electrostatic charges on insulators and isolated (non-grounded) conductors to reduce the magnitude of electrostatic discharges in the ESD protected area.

  • Compressed air ionizers use compressed air to combat electrostatic attraction neutralizing charges on particles causing contamination or visual defects on products.
  • Benchtop and Overhead Ionizers produce positively and negatively charged ions that are moved to the work area with fan driven airflow.
  • Laminar Flow Ionization Bars are used with Laminar Flow Hoods, controlled chambers and other contained applications.
  • Room Ionization reduces electrostatic discharge (ESD) and electrostatic attraction (ESA) in cleanroom environments.

Our sales reps are outfitted with ionizers to demonstrate how ionization can benefit your ESD Control Plan. If you are interested in a demo and/or more information on a Desco product please contact us HERE.

You’re invited to the Texas ESD Association Local Chapter Tutorial Program!

March 4-5, 2014

3M innovation Center Austin TX

  • Fundamental handling practices to reduce the risk of ESD damage
  • Installing the most basic ESD control program (ESD control on a shoestring budget)
  • Simplified measurements to ensure that an ESD control program is working and a review of best practices used by major companies today
  • Auditing an ESD control program

Practical ESD information for small to midsize electronic related companies!

3M Innovation Center
6801 River Place Blvd.
Austin, TX 78726

Registration Fees
1/2 Day (1 Tutorial) $250
1 full Day (March 4 -or- March 5) $450
Both Days (4 Tutorials) $800

Register – Click Here for more Information

You’re invited to the ESD Association Regional Tutorials

February 26-27, 2014

EOS/ESD Association Inc.

7900 Turin Rd. Bld 3 Rome NY 13440

  • ESD Basics for the Program Manager
  • How To’s of In-Plant ESD Survey and Evaluation Measurements

Make sure you have people with the right knowledge to maintain your ESD control program at the highest level.

Learn from top industry professionals.

ESDA Certification courses are part of the globally recognized Certified Professional Program Manager Program developed by the ESD Association.

EOS/ESD Association Inc.
7900 Turin Rd. Bld 3
Rome NY 13440

Register – Click Here for more Information

Is It OK to Connect Wrist Strap to Mat Using Alligator Clip?

Alligator Clip Connected to Mat

Alligator Clip Connected to Mat – Poor Practice

Correct Wrist Strap Setup

Correct Wrist Strap Setup

If testing can demonstrate that operator’s resistance path is reliable, it might be OK, but it is certainly not best practice. Alligator clip attached to dissipative mat is not recommended per ESD Handbook ESD TR20.20 wrist strap section 5.3.2.2.2 Wrist Strap Ground Cord: “The groundable end of the cord is most often equipped with a banana plug and a mating alligator clip. Any electrical connector that could be attached to ground would be acceptable as long as it was mechanically durable. The preferred grounding point for the groundable end of the cord would be a common point ground as defined in ANSI/ESD S6.1.

NOTE: Many wrist strap users clip the wrist cord to the edge of an ESD protective mat. This process is not recommended as it can increase the total system resistance to ground to over the 35-megohm limit required in ANSI/ESD S20.20.”

Here’s additional pertinent information:

“Wrist strap ground cords must be connected to a groundable point or an equipotential bonding point. Do not connect to a snap on a dissipative mat unless it is the groundable point for the mat. Do not clip a wrist strap to the edge of a dissipative mat.” [ESD Handbook ESD TR20.20 wrist strap section 5.3.2.7 Wrist Strap Summary]

Due to it lower retention force than installed in a banana jack, attaching a wrist strap cord to a mat with an alligator clip is problematic.

“The first step in ensuring that everything in an EPA [ESD protected area] is at the same electrical potential is to ground all conductive components of the work area (i.e., worksurfaces, people, equipment, etc.) to the same electrical ground point. This point is called the common point ground and is defined by ANSI/ESD S6.1 as ‘a system or method for connecting two or more grounding conductors to the same electrical potential.’ …The next step in completing the ground circuit is to connect the common point ground to the AC equipment ground or an auxiliary ground, as defined in ANSI/ESD S6.1.” [ESD Handbook ESD TR20.20 grounding section 5.1.3 Basic Grounding Requirements]

“The primary method of static charge control is direct connection to ground for conductors, static dissipative materials, and personnel.” [ESD Handbook ESD TR20.20 section 5.3.6]

Per JESD625-A section 7.6 ESD ground connections “Firm fitting connecting devices such as metallic crimps, snaps and banana plugs shall be connected to designated ground points. Wire splices should be crimped or soldered. Use of alligator clips is not recommended.”

Per JESD625-A section 7.3 ESD protected workstation ESD ground “The design and construction of the grounded ESD protected workstation and associated equipment shall ensure that all external parts, surfaces, and shields of electrical equipment and power tools are at ground potential at all times. Each ESD workstation shall be individually connected to the ESD ground. When more than one ESD worksurface is used at a workstation, each surface shall be individually connected to the ESD ground.”


To see a full list of Wrist Straps and recommended Coil Cords offered by Desco – Click Here

To see a full list of Ground Cords offered by Desco – Click Here

Should dissipative hats be worn to protect ESD sensitive items from charges on hair?

ANSI/ESD S20.20 doesn’t mention hair, but the ESD Handbook ESD TR20.20 does. The general rule from ANSI/ESD S20.20 is in section 8.3.

From ESD Handbook ESD TR20.20 mentions “human hair” is near the extreme end of the Triboelectric Series, so it can be high charging. But the above rule would apply; keep hair 12” away from ESD sensitive items. ANSI/ESD S20.20 says:

“In order to mitigate field-induced CDM [Charged Device Model] damage, the ESD program shall include a plan for the handling of process-required insulators. If the field exceeds 2,000 volts/inch, steps shall be taken to either:

A) Separate the insulator from the ESD-sensitive device by a distance of 30 cm (12 inches);
or
B) Use ionization or other charge mitigating techniques to neutralize the charge.”

If the person is grounded, will the charge on the hair be removed to ground?  No. An insulator, hair being a non-conductor, cannot be grounded. The charge on a person’s hair would remain being slowly neutralized by natural ions in the air.

The hair question is similar to clothing which is almost always insulative. The clothing cannot be grounded. We say that the charge stays on the person’s clothing, but if covered by a Statshield ESD Smock that like a Faraday Cage, the fabric shields the charges from the ESD sensitive items. Technically, with the conductive fibers in the fabric, the charge is attenuated.

The technical information on dissipative hats would be would be similar to ESD smocks. “Garments are intended to attenuate electrostatic fields that may be present on personnel clothing. … While a person may be grounded using a wrist strap or other grounding methods, that does not mean that insulative clothing fabrics can dissipate a charge to that person’s skin and then to ground. Personnel clothing usually is electrically separate or isolated from the body.” [ESD TR20.20 section 5.3.13.1]

Regarding contamination, the handbook includes “Skin flakes, hair, biological pathogens and other human contamination continues to be the source of many contamination problems. Industry has recognized this problem and taken steps to protect contamination sensitive products from being adulterated by human hands and fingers.” [ESD Handbook ESD TR20.20 ESD Glove section 5.3.15.1 Introduction]

Visit to http://desco.descoindustries.com/Standards.aspx and from www.ESDA.org one can obtain complimentary downloads standards.

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