ANSI ESD-S20.20-2021-EN.pdf - 第6页

ANSI/ESD S20.20- 2021 ii For more infor mation on t he requ irements in this stand ard, there is a techn ical report, ESD TR20.20 – ESD Association Technic al Report – Handbook for the Development of an Electrostatic Dis…

ANSI/ESD S20.20-2021

(This foreword is not part of ESD Association Standard ANSI/ESD S20.20-2021)

FOREWORD

This standard covers the requirements necessary to establish, implement, and maintain an

electrostatic discharge (ESD) control program for activities that manufacture, process, assemble,

install, transport, package, label, service, test, inspect, or otherwise handle electrical or electronic

parts, assemblies, and equipment susceptible to damage by electrostatic discharges greater than

or equal to 100 volts human body model (HBM) and 200 volts charged device model (CDM). The

CDM voltage level used in this document is based on managing process essential insulators to

mitigate field-induced voltages on devices that could lead to damage.

This standard also defines the requirements for isolated conductors. The reference to machine

model (MM) is retained in this standard for the historical association to the MM robustness of

devices to isolated conductors.

HBM and CDM fully characterize the ESD robustness of devices. Therefore, MM testing is no longer

required to qualify devices, and test data may not be available.

This document covers the ESD control program requirements for establishing a program to handle

ESD sensitive (ESDS) items based on the historical experience of both military and commercial

organizations. References include EOS/ESD Association, U.S. Military, and ANSI approved

standards for material properties and test methods. The fundamental ESD control principles that

form the basis of this document are:

A. All conductors in the environment, including personnel, shall be bonded or electrically

connected and attached to a known ground or contrived ground (as on shipboard or aircraft).

This attachment creates an equipotential balance between all items and personnel.

Electrostatic protection can be maintained at a potential above a "zero" voltage ground potential

if all items in the system are at the same potential.

B. Process essential insulators in the environment cannot lose their electrostatic charge by

attachment to ground. Ionization systems provide neutralization of charge on these process

essential insulators (circuit board materials and some device packages are examples of

necessary insulators). Assessment of the ESD hazard created by electrostatic charge on the

process essential insulators in the workplace is required to ensure that appropriate actions are

implemented, commensurate with the risk to ESDS items.

C. Transportation of ESDS items necessitates enclosures in protective materials, although the

type of material depends on the situation and destination. While these materials are not

discussed in the document, it is important to recognize the differences in applications. For more

clarification, see ANSI/ESD S541.

Any relative motion and physical separation of materials or flow of solids, liquids, or particle-laden

gases can generate an electrostatic charge. Common sources of electrostatic charge include

personnel, items made from common polymeric materials, and processing equipment. ESD

damage can occur in several ways, including:

i. A charged object (including a person) coming into contact with an ESDS item.

ii. A charged ESDS item making contact with ground or another conductive object at a different

potential.

iii. An ESDS item making contact with ground or another conductive object while exposed to an

electrostatic field.

Examples of ESDS items include, but are not limited to, microcircuits, discrete semiconductors,

thick and thin film resistors, hybrid devices, printed circuit boards, and piezoelectric crystals. It is

possible to determine device and item susceptibility by exposing the item to simulated ESD events.

The level of sensitivity, determined by testing using simulated ESD events, may not necessarily

relate to the level of sensitivity in a real-life situation. However, the sensitivity levels are used to

establish a baseline of susceptibility data to compare devices with equivalent part numbers from

different manufacturers. Two different models are used for the characterization of electronic items:

HBM and CDM.

ANSI/ESD S20.20-2021

For more information on the requirements in this standard, there is a technical report, ESD TR20.20

– ESD Association Technical Report – Handbook for the Development of an Electrostatic Discharge

Control Program for the Protection of Electronic Parts, Assemblies, and Equipment.

Compliance with this standard can be demonstrated through third-party certification. The

certification process is like any quality management system certification such as ISO 9001.

Information on the certification process can be obtained by contacting an EOS/ESD Association,

Inc. approved certification body. For a list of EOS/ESD Association, Inc. approved certification

bodies, see www.esda.org.

This standard

was originally designated ANSI/ESD S20.20-1999 and was approved on August 4,

1999. ANSI/ESD S20.20-2007 was a revision of ANSI/ESD S20.20-1999 and was approved on

February 11, 2007. ANSI/ESD S20.20-2014 is a revision of ANSI/ESD S20.20-2007 and was

approved on March 25, 2016. ANSI/ESD S20.20-2021 is a revision of ANSI/ESD S20.20-2014 and

was approved on October 28, 2021.

At the time, the ANSI/ESD S20.20-2021 was prepared, the 20.20 ESD control program

Subcommittee had the following members:

John T. Kinnear, Jr., Chair

IBM

Christopher Almeras

Raytheon

Kevin Duncan

Seagate Technology

Reinhold Gaertner

Infineon Technologies AG

Steven Gerken

Ron Gibson

Advanced Static Control

Consulting

David Girard

Staticon Support Services,

Inc.

Fatjon (Toni) Gurga

Reliant ESD

Ginger Hansel

Dangelmayer Associates

Shane Heinle

Digi-Key Corporation

Matt Jane

Tesla

Gary Latta

SAIC

Michael Manders

The United States Air Force

Chuck McClain

Micron Semiconductor

Robert "Hank" Mead

BAE Systems, Inc.

Ronnie Millsaps

Carl Newberg

Simco-Ion

Andrew Nold

Teradyne, Inc.

Daniel O'Brien

University of Dayton

Research Institute

Dale Parkin

Seagate Technology

Nathaniel Peachey

Qorvo

Keith Peterson

Missile Defense Agency

Wolfgang Stadler

Intel Deutschland GmbH

Matt Strickland

The Boeing Company

David E. Swenson

Affinity Static Control

Consulting, LLC

Terry Welsher

Dangelmayer Associates

Craig Zander

Transforming Technologies

ESD Association Standard (S): 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.

ANSI/ESD S20.20-2021

iii

The following individuals contributed to the development of ANSI/ESD S20.20-2014, ANSI/ESD

S20.20-2007, and/or ANSI/ESD S20.20-1999.

Brent Beamer

Donald E. Cross

USN

Robert Cummings

NASA

Kevin Duncan

Seagate Technology

Reinhold Gaertner

Infineon Technologies

Steve Gerken

USAF

Ron Gibson

Advanced Static Control

Consulting

Tim Jarrett

Boston Scientific

Ronald L. Johnson

Intel

John T. Kinnear, Jr.

IBM

Anthony Klinowski

Boeing

Dave Leeson, Co-Chairman

Motorola SSTG

Garry McGuire

NASA

(Hernandez Engineering)

Thomas Mohler

Raytheon Systems

Corporation

Ralph Myers

ASC

Gene Monroe

NASA – LARC

Carl Newberg

MicroStat Laboratories

Dale Parkin

Seagate Technology

Robert Parr

Consultant

Brian Retzlaff

Plexus

Jeffrey Scanlon

ASC

Jeremy Smallwood

Electrostatic Solutions Ltd.

David E. Swenson

Affinity Static Control

Consulting, LLC

Sam Theabo

Plexus

Scott Ward

Texas Instruments

Joel Weidendorf

River's Edge Technical

Service

Craig Zander

Transforming Technologies

Sheryl Zayic

Boeing