alu esd handbook

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ESD HandbookIssue 13

October 2008

Disclaimers

It is the responsibility of the user of this document to verify that it is the most current edition.Any document printed from the Document Control System is an uncontrolled copy.

ALCATEL-LUCENT ESD CONTROL HANDBOOK ISSUE 13 Classification= OPENi


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Cover:ISSUE 13 October 2008.COVER The cover shows the city of Tucson, AZ, USA as alocal storm generates multiple lightning strikes.

Lightning strikes are the ultimate in large scale Electro-Static Discharges. They induce hugeelectrical impulses on electrical distribution networks. These impulses find their way into ourproducts. Mitigation of these types of stresses in the form of gas discharge tubes, earth grounds/shields, spark gaps, and fast acting solid state on board protector diodes are a portion of themethods we take to ensure the reliable operation of our products.

ALCATEL-LUCENT ESD CONTROL HANDBOOK ISSUE 13 Classification= OPENii


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CONTENTS

SCOPE..................................................................................................................................................... 5PREFACE................................................................................................................................................ 5HISTORY & ACKNOWLEDGEMENTS............... ............. ............. ............. ............. .............. ............. ... 5REASONS FOR REISSUE......... ............. ............. ............. ............. ............. ............. ............. ............. ...... 6INTRODUCTION... .............. ............. .............. ............. .............. ............. ............. .............. ............ ......... 7

Critical Factors for Managing a Successful ESD Control Program.............. .............. ............. .............. .. 8Alcatel-Lucent ESD Program Elements............ ............. .............. ............. .............. ............. ............. ..... 8

ALCATEL-LUCENT ESD POLICY............ .............. ............. .............. ............. .............. ............. ........... 9Policy................................................................................................................................................... 9Intent....................................................................................................................................................9Responsibilities ....................................................................................................................................9

ALCATEL-LUCENT ESD LEADERSHIP TEAM MISSION STATEMENT............. .............. .............. 10BASIC ESD CONCEPTS... ............. ............. .............. ............. .............. ............. .............. ............ .......... 11

Definition ........................................................................................................................................... 11Causes of ESD......... .............. ............. .............. ............. ............. .............. ............. ............ .............. ... 11Triboelectric Charging.............. ............. .............. ............. .............. ............. ............. .............. ............ 12Static Potential...................... .............. ............. ............. ............. ............. .............. ............. .............. ... 12Static Charge ...................................................................................................................................... 12

ESD FAILURE MODELS............. ............. .............. ............. ............. .............. ............. .............. ........... 14Introduction........................................................................................................................................ 14Human Body Model ........................................................................................................................... 14Charged-Device Model (CDM) by Direct Contact.............. .............. ............. .............. .............. .......... 16CDM by Static Induction .................................................................................................................... 17Machine Model (MM) ........................................................................................................................ 18

SOURCES OF ESD DAMAGE.......... ............. .............. ............. .............. ............. ............. .............. ...... 19Environmental Conditions....................... ............. ............. .............. ............. .............. ............. ............ 19Device Sensitivity.......... .............. ............. .............. ............. ............. .............. ............. ............. .......... 19Static Shock................. .............. ............. .............. ............. ............. .............. ............. ............. ............ 22ESD in clean rooms and its Effects on IC Wafers ............ ............. ............. .............. ............. ............. .. 22

ESD EFFECTS............ ............. .............. ............. .............. ............. ............. .............. ............ .............. ... 23ESD CONTROL REQUIREMENTS AND TECHNIQUES ............ ............. ............. ............. .............. ... 24

Introduction........................................................................................................................................ 24Designed-In Protection ....................................................................................................................... 24Basic Rules for ESD Control................. ............. .............. ............. ............. .............. ............. ............. . 24Static-Safe.......................................................................................................................................... 25Antistatic Property...... ............. ............. .............. ............. .............. ............. .............. ............ ............. . 25Static Conductors and Nonconductors............ .............. ............. ............. .............. ............. ............. ..... 25Surface Resistivity ............. ............. ............. ............. ............. .............. ............. ............. ............. ........ 25Conductive Materials..... ............. .............. ............. ............. .............. ............. .............. ............. .......... 26Static-Dissipative Materials ................................................................................................................ 26System Level Testing............... ............. ............. .............. ............. .............. ............. ............. ............. . 26Device Testing............... .............. ............. .............. ............. .............. ............. ............. ............. .......... 26

ESD CONTROL REQUIREMENTS SPECIFIED BY CLASS............ .............. ............. .............. ........... 271.0 Work Area Classification....................... .............. ............. .............. ............. ............. .............. . 27

2.0 Personnel Training Program .................................................................................................... 303.0 Personnel Certification ............................................................................................................ 304.0 Auditing.................................................................................................................................. 305.0 Statistical Process Control ............ .............. ............. .............. .............. ............. .............. ......... 306.0 Production Equipment Certification ............. ............. .............. .............. ............. .............. ....... 317.0 Personnel Grounding............................................................................................................... 328.0 Flooring, Finishes, Carpeting and Mats............... ............. .............. .............. ............. .............. . 349.0 Transporting Products............. .............. ............. .............. ............. ............. .............. ............. ... 3510.0 ESD Grounding Requirements and Methods ............. ............. .............. ............. ............. .......... 3711.0 Static-Generating Material Control .............. ............. ............. .............. ............. .............. ......... 38

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ALCATEL-LUCENT ESD CONTROL HANDBOOK ISSUE 13 Classification= OPENiv

12.0 Dissipative Work Surfaces.................. ............. ............. ............. ............. .............. ............. ...... 3813.0 Dissipative Gold Finger Shunts.................... .............. .............. ............. .............. ............. ........ 3914.0 Extraordinary Measures (Class 0 Devices) ............. .............. ............. ............. .............. ............ 3915.0 Other Controls................... ............. ............. ............. .............. ............. ............. ............. .......... 3915.0 Installation Standards .............................................................................................................. 40

CENTRAL OFFICE AND OFF SITE GUIDELINES................. .............. ............. ............. ............. ........ 40ALCATEL-LUCENT ESD LEADERSHIP TEAM ............. .............. ............. .............. ............. .............. 42

APPENDIX A DEFINITION OF TERMS ............. .............. ............. .............. ............. .............. .......... 43APPENDIX B ASSOCIATED COMPANY DOCUMENTATION.............. ............. .............. ............. . 47APPENDIX C REFERENCES.................. ............. ............. .............. ............. ............. ............. ............ 48ESD ASSOCIATION STANDARDS ............ ............. ............. ............. .............. ............. ............. .......... 52

LIST OF FIGURES

Figure 1 - Separated Roll of Cellophane Tape .................................................................................. 11Figure 2 - Equivalent Circuit of Human Body Model ......................................................................... 15Figure 3 - Equivalent Circuit of Charged-Device Model.................................................................... 17Figure 4 - ESD by Induction ................................................................................................................ 18Figure 5 - Effects of ESD Caused Failures ........................................................................................ 23

LIST OF TABLES

Table A - Triboelectric Series for Some Common Materials ............................................................ 13Table B - Typical Electrostatic Voltages............................................................................................. 15Table C - Typical Charge Generators ................................................................................................ 20Table D - Device Sensitivity ................................................................................................................ 20Table E - HBM...................................................................................................................................... 21Table F - CDM...................................................................................................................................... 21Table G - ESD Control Requirements Specified by Class................................................................ 29


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SCOPEThis Electrostatic discharge control Handbook is the controlling document for the Alcatel-LucentElectrostatic Discharge (ESD) Control program and applies to all facets of our business. Minimumrequirements are established here for proper ESD control techniques. This handbook is intended forengineering, management, and training personnel, and shall be used to implement local ESDprograms. Further details are contained in the Alcatel-Lucent ESD Inspection Guide.

PREFACE

This handbook defines and describes Electrostatic Discharge (ESD) and its effects on electronicdevices. ESD causes are explored, numerous sources of static charges found at the workplace areidentified, and how these charges threaten sensitive electronic devices are discussed. Generalrequirements are specified for controlling ESD damage, and detailed instructions are given for eachtechnique.

This handbook supports Alcatel-Lucent policy, which states that each organization shall use properESD control measures when handling ESD sensitive products and that all-new design shall bequalified for adequate designed-in ESD protection. Alcatel-Lucent recognizes that special procedures

and methods may be required for certain personnel, including the physically impaired, and may not becovered in this document. The local ESD coordinator shall develop the necessary procedures andmethods to ensure compliance with the intent of this document.

HISTORY & ACKNOWLEDGEMENTS

The original version of this handbook was based on the Merrimack Valley ESD Control Handbookdrafted by Ted Dangelmayer and Joe Doucette, Jr.

Copyright 2008 Alcatel-Lucent Inc.

All Rights Reserved.

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REASONS FOR REISSUE

The following revisions or additions have been incorporated into ISSUE 13 of the Alcatel-Lucent

Electrostatic Discharge Control Handbook.

1) Section 1 Work area Classification has been updated to be in alignment with QMS

instructions.

2) Section 3.1 has been updated to reflect ESD training re-certification is to be at a minimum

of every two years (Issue 12 guidance was every year).

3) Leadership Team update

4) Added Open Classification to this document for compliance with the October 20 directive

for classification marking of documents.

5) The following sections had verbiage changed with out any substantive changes for

alignment with QMS L2-09:

6.1

7.4

7.5

8.1

9.2


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INTRODUCTION

Electrostatic Discharge (ESD) poses a serious problem to industries that use electronic devices. Manydevices are highly sensitive to damage from the discharge of static electricity, which usually cannot be

seen or felt. ESD affects many components such as diodes, transistors, integrated circuit devices,metal-oxide-semiconductors (MOS), optoelectronic devices (lasers and photodiodes), surface acousticwave (SAW) filters, and film passive components, etc. ESD can also damage semiconductor wafersand integrated circuit photo-masks. These damaging effects are well documented. Device failures donot always occur immediately; often, the component is only slightly weakened or altered, but is lessable to withstand subsequent ESD exposure and may constitute a reliability problem.

It is essential that everyone in the product life cycle (design & development, manufacturing, integration,distribution, installation, and repair) be concerned with ESD. The Alcatel-Lucent procedure for ESDsensitive products is Hands Off. It prohibits anyone from directly contacting ESD sensitive productsfor any reason (or at any time) without taking appropriate ESD precautions.

Alcatel-Lucent is striving to eliminate device failure caused by ESD damage. By reducing the failure

rate of individual components, we enhance the reliability of our products, which in turn improvescustomer satisfaction. It is necessary to understand ESD and its inherent dangers before successfulcontrol techniques can be put into practice. This handbook provides an awareness of ESD conceptsand specific instructions for combating ESD induced failures.

Since these instructions are considered minimum requirements and preferred ranges are statedthroughout this document, Alcatel-Lucent organization specific (local) and supplier requirements maybe more stringent. Engineering analysis must be performed when defining local requirements that areoutside the preferred ranges. The documentation of work area classification is the responsibility of localand supplier engineering and is defined under Work Area Classification.

This document is not to be considered an in-depth knowledge base for ESD education, and does notpurport to replace certified ESD Training Courses.


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Cri t ical Factor s for Managing a Succ essful ESD Con trol Program

Experience has shown that 12 critical factors form the basis of a successful ESD control program. (Seethe following list.) These 12 factors are described in greater detail in the Alcatel-Lucent ESDInspection Guide and ESD Program Management (see Appendix B).

Factor 1An Effective Implementation Plan

Factor 2 Management CommitmentsFactor 3A designated ESD Engineering Coordinator/ConsultantFactor 4An Active ESD Control CommitteeFactor 5 Realistic RequirementsFactor 6 Training for Measurable GoalsFactor 7Auditing Using Scientific Measures

7.1 General Program Analysis7.2 Work Area Inspections7.3 A Facility Qualification Program7.4 Product Design Review

Factor 8 ESD Test FacilitiesFactor 9A Communication Program

Factor 10 Systemic PlanningFactor 11 Human Factors EngineeringFactor 12 Continuous Improvement

Alcatel-Luc ent ESD Program Elements

For emphasis, the 12 critical factors may be segmented into four main elements and should be used byeach location as a checklist to verify that their program meets customer expectations. The elementsare:

Demonstrable compliance with the policies and procedures in this handbook

An auditing program based on the ALCATEL-LUCENT ESD INSPECTION GUIDE orequivalent self-assessment program

A formal manufacturing acceptance procedure for verifying that designs comply withappropriate standards

Documentation and personnel awareness of work area classifications and procedures basedon local specifications

Bell Communications Research has recognized the Alcatel-Lucent ESD control program as meetingthe intent of the requirements in BR-GR-1421-CORE, Generic Requirements for ESD ProtectiveWorkstations.


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ALCATEL-LUCENT ESD POLICY

Pol icy

One of the strengths of Alcatel-Lucent products and services has always been Alcatel-Lucent continuingcommitment to high quality and reliability. Central to that is Electrostatic Discharge (ESD) control andprevention. It is therefore, our policy to:

Consistently provide components and systems that are sufficiently ESD design hardened to meetthe quality and reliability expectations of our customers.

Consistently adhere to the proper ESD handling, storage, packaging, and transportation techniquesthroughout all facets of our business.

Intent

ESD is known to affect electronic components and systems in a variety of ways and is heavily influenced bytechnology, design and handling techniques. Therefore, we will strive for continual improvement inprevention techniques, employee awareness and designed-in-protection at all levels of our company. It isour intention to maintain Alcatel-Lucent as a World Class leader in ESD control and design.

This will require the adherence to appropriate design standards as well as controlling the environmentaround which electronic products are designed, manufactured, transported, and used. To satisfy this intent,we will need to comply with documents such as the Alcatel-Lucent ESD Control Handbook, the Alcatel-Lucent ESD Inspection guide, and all appropriate Alcatel-Lucent product specifications and best currentpractices. We will strive to provide products and services that are sufficiently ESD robust in design and freeof any latent ESD handling defects to give our customers significant economic advantages in their market.

Responsibi l i t ies

Each business group president, entity head, and senior staff officer is responsible for:

Communicating the policy and seeing that it is carried out effectively

Providing adequate support and resources.

Each member of management is responsible for:

Ensuring adequate design qualification of our product offerings

Setting the example by always complying with the handling procedures in the Alcatel-Lucent ESD

Control Handbook

Communicating our ESD policy to each employee, visitor and supplier

Clarifying specific responsibilities for ESD prevention, awareness and design

Establishing effective ESD process controlsEnsuring consistent compliance with the Alcatel-Lucent ESD policy and initiating corrective action ifneeded

Implementing and reviewing specific ESD improvement programs

Providing education and training in ESD awareness and prevention for employees.

The Alcatel-Lucent ESD Leadership Team is responsible for overall leadership and direction of the ESDprogram.


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ALCATEL-LUCENT ESD LEADERSHIP TEAM MISSION

STATEMENT

The mission of Alcatel-Lucent ESD Leadership Team is to provide overall leadership and direction andto network technical resources for the ESD program. The team supports Alcatel-Lucents customersatisfaction and reliability objectives by facilitating the continuous improvement and consistentimplementation of the ESD policies and procedures as defined in the Alcatel-Lucent ESD Control

Handbook, Inspection Guide, and X-Specifications.

ALCATEL-LUCENT ESD CONTROL HANDBOOK ISSUE 13 CLASSIFICATION= OPENPage 10 of

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Please refer to page 42 for a current listing of the Alcatel-Lucent ESD Leadership Team members.


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BASIC ESD CONCEPTS

Defini t ion

Electrostatic Discharge (ESD) is a sudden transfer of charge between two objects. A familiar exampleis the zap that is felt after sliding across a car seat and touching the door handle. While sliding, thebody becomes charged, and this charge suddenly jumps when the body encounters an uncharged oroppositely charged object (the door handle). Dry climatic conditions aggravate the problem becausedry ambient air inhibits surface charge leakage and large static potentials result. Often the dischargecannot be felt, but it may still damage sensitive electronic devices.

Causes o f ESD

Static charge is generated whenever two different materials come into contact or are rubbed togetherand then separated, such as an unrolling cellophane tape as shown in Figure 1 Separated Roll ofCellophane Tape.

Figure 1 - Separated Roll of Cellophane Tape

(Showing Distribution of Positive and Negative Charges)


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Triboelectr ic Charging

Static charge accumulation, known as triboelectric charging, results from the transfer of electrons fromone material to another. Table A - Triboelectric Series for Some Common Materials shows thetriboelectric series of some common materials. Note that static electricity is a surface phenomenon,and static charge accumulates only on the outer surface of an object, not throughout the object.

Generally, static charge accumulation can occur between any two materials. These materials may besolids, liquids or gases, so static electricity is always present. To understand the static charge behaviorof materials, their relative positions in the triboelectric series must be determined. The polarity (+ or -)of the static charge generated on each of the materials and the relative magnitude of the charge canbe obtained from Table A - Triboelectric Series for Some Common Materials. The farther apart thematerials are located in the series, the greater the magnitude of the charge. Also, a material at the topof the scale acquires a positive charge with respect to any material below it. A classic example isrubbing a glass rod with wool. The glass assumes a positive charge and the wool a negative charge.Many materials in Table 'A' are commonly used in electronics manufacturing.

Static Potential

The accumulated electrical charge causes a static potential to develop. The static potential is not withrespect to ground, but is a potential difference between any two different objects. ESD occurs when theaccumulated charge is transferred to another object with a different electric potential.

Static Charge

The potential difference between two separated objects can be modeled as the voltage between thecharged plates of a capacitor. With a given charge (Q), the static potential (V) developed between twomaterials depends on the capacitance (C) between these two materials, such that Q=CV. For a givencharge (Q), C and V depend on the environment and may vary, but the product CV remains constant.


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TABLE A

TRIBOELECTRIC SERIESFOR SOME COMMON MATERIALS

MATERIALS + POLARITY

Acetate

Human HairNylonWoolFurLeadSilk

AluminumPaperPolyurethaneCottonWood

SteelHard rubber

Acetate FiberMYLAR*Epoxy GlassNickel, Copper, SilverBrass, Stainless SteelSynthetic Rubber

AcrylicPolystyrene FoamPolyurethane Foam

Saran wrapPolyesterPolyethylenePolypropylenePVCTEFLON*Silicone Rubber

Acquires a more

positive charge+

Acquires a morenegative charge

* Registered trademark of E.I. Du Pont De Nemours.

Table A - Triboelectric Series for Some Common Materials


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ESD FAILURE MODELS

Int roduct ion

Three generalized models have been suggested for ESD events that can cause device damage orfailure. These models are:

Human Body Model (HBM)

Charged-Device Model (CDM), including CDM by Direct contact, and CDM by static induction

Machine Model (MM)

To better understand how ESD occurs and what preventive measures to use, it is important to knowthe basics of these models. The variations between models, discharge parameters, failuremechanisms and device testing for each model are given in the following paragraphs.

Human Bod y Model

A person can develop a significant charge with simple movements. Table A - Triboelectric Series forSome Common Materials shows the magnitude of charge buildup that can result from simpleoperations (for example, walk, sitting, unpacking, etc.). When a charged individual touches a device, asin a hand-assembly operation, some of the energy stored on the individuals body is transferred ordischarged either to the device or through the device to ground. It is possible to develop human bodypotentials that far exceed damage ratings of the device. Some protection is provided by networks builtinto many integrated circuits (ICs). This protection is adequate for some operations, but not for all.Often, the discharge pulse contains enough power to alter device parameters, melt silicon junctions orcause electrothermomigration.

The HBM equivalent circuit used to describe this event is illustrated in

Figure 2 - Equivalent Circuit of Human Body Model. In the current industry standard, the HBMequivalent circuit contains a 1500-ohm resistor and a 100-picofarad (pF) capacitor. These componentsrepresent the effective resistance and capacitance of the human body. (Other resistance andcapacitance values have been used in the past for example, 300 to 10 kilohms and 100 to 400 pF.)The contact resistance is usually less than 5 ohms. Another important element of the event is thedynamic resistance of the discharge arc, which is typically 100-200 ohms. Compared to the charged-device model (CDM), the HBM is a slow event (rise time = 10 nanoseconds, width = 150nanoseconds).

The HBM equivalent circuit usually assumes that the discharge occurs to a single lead while one ormore leads are connected to ground. Although this circuit does exist, the more likely circuitarrangement is a discharge path through a land with all other leads floating. An HBM dischargethrough a device to ground is usually more damaging than an HBM discharge through a floatingdevice.


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TABLE B

TYPICAL ELECTROSTATIC VOLTAGES (VOLTS)RELATIVE HUMIDITY

EVENT10% 40%*

55%Walking across carpet 35,000 15,000 7,500

Walking across vinyl floor 12,000 5,000 3,000Motion of bench worker 6,000 600 400

Removing DIPs* from plastic tubes 2,000 700 400

Removing DIPs from vinyl trays 11,500 4,000 2,000

Removing DIPs from STYROFOAM 14,000 5,000 3,500

Removing bubble pack from PWBs 26,000 20,000 7,000

Packing PWBs in foam-lined box 21,000 11,000 5,500

* Dual in-line packages Registered trademark of Dow Chemical Co. Printed wiring boards

Table B - Typical Electrostatic Voltages

Work Surface

IC

Charged personnel (ungrounded) zapping a module placed on awork surface (discharge from finger to pin to chip to work surface).

BodyDevice

Current Pulse

Figure 2 - Equivalent Circuit of Human Body Model


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*See JEDEC Standard No. 625-A/NOTE The recommended minimum humidity is 40% R.H.


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Charged-Device Model (CDM) by Direct Contact

A second ESD failure model is associated with the device and package itself. In its pure form, thecharged-device model assumes a charge on its lead frame and other conductive paths that is quicklydischarged through one pin to ground. Here the charge residing on the metal parts of the device flowsthrough and creates failures of junctions, dielectrics and components that are part of the discharge

path.

The CDM is intended to simulate charging/discharging events that occur in production equipment andprocesses. The classic example of this is a device sliding down a shipping tube. However,opportunities for such events vary widely with the types of processes being considered and, unlikepersonnel grounding, may not be under the control of the facility ESD coordinator.

The parameters in the CDM equivalent circuit are largely dependent on the device package and itsinternal configuration. The CDM produces a much faster pulse than the HBM (rise time < 100picoseconds, with = 2 nanoseconds). Because of this, the CDM is more likely to produce dielectricbreakdown of gate oxides and to bypass HBM-based protection circuitry to cause internal (and notimmediately detectable) failures. Most recent ESD failures reported in the industry have been causedby CDM-type events. A list of references to CDM field failures is given in the References.

The HBM discussion considered a floating device and the possibility of transferring enough energyfrom the human body to damage a device. Even if the floating device is not damaged on contact, thedevice is consequently charged, and there exists the possibility of damage when discharged. Damageor failure thresholds for the CDM may be considerably different from those determined by the HBM.

Sliding in a shipping tube, sliding on work surfaces or by sharing charges with people or objects duringassembly operations, can charge devices. The charge acquired is either mobile or immobile. Themobile charge is on the metal lead frame and conductors, and the immobile charge is on thenonconductive portions of the device. The immobile charge can induce a potential on the conductiveparts of the component by static induction. See CDM by Static Induction.

Devices are generally uploaded from shipping tubes into handlers or insertion equipment. A chargeddevice eventually contacts an effective ground in the machine and discharges. The corner pins on a

device are most likely to contact a ground first. As a result, many devices fail because of damageassociated with corner pins.

The capacitance of the device package at the instant of grounding plays a strong role in determiningthe energy released during the ESD event and whether the threshold for damage will be exceeded.Charging a package device while it is positioned near ground and them moving it away from groundwill have the effect of increasing the potential as well as increasing the energy stored on the device.The discharge will be more damaging than it would be if the device were discharged near ground. Theincrease in potential and energy is inversely proportional to the capacitance ratio. Although the deviceenergy storage capacity is limited in the CDM (when compared to the HBM), the discharge pulse canoccur so fast that the protection circuit does not turn on and the power density exceeds the damagethreshold of an unprotected circuit element such as a gate oxide.


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The CDM equivalent circuit used to describe this phenomenon is illustrated in Figure 3. It contains adevice capacitance (1-60 pF, depending on the package type). Note that human body capacitance andresistance are not considered in the CDM. In addition, device inductance ranges from 5 to 50nanohenries, and contact resistance is still 0.1 to 5 ohms. The device resistance of 50 to 300 ohms,while not considered in the HBM, now has a more significant role in the CDM; it has a considerableeffect on the series-LCR circuit formed by the device.

Contact ResistanceDevice

Current Pulse

Figure 3 - Equivalent Circuit of Charged-Device Model

CDM by Stat ic Induc t ion

An external field can affect a device in two ways. First, gate structures on a device inserted in the fieldcan develop potentials, the magnitude of which depends on the division of capacitance between thefield source and ground. Under high fields and close spacing with sensitive devices, dielectricbreakdown can occur. However this failure is not common.

An ESD by induction is the second (and more likely) way in which failure can occur. This series ofevents is illustrated in Figure 4. In this process, a neutral (uncharged) object (such as an IC) is placednear a static charge that resides on an insulator in the work area. The resulting field from this staticcharge will cause (induce) a charge separation to occur on the lead frame and conductors of thedevice. If a device lead is then grounded, a current will flow. The charges that are of the same polarityas the static charge are driven to ground by the field. The current flow is equivalent to a CDM event asdescribed previously. However, the threat to the device does not end here. The object now has a net

residual charge until it dissipates into the air or is grounded in a later process step. If the latter occurs,the result is a second event, opposite in polarity and equal in magnitude (charge) to the previous one.Thus, ESD by induction can result in a double jeopardy for devices. Threshold data by CDM testingalso applies to this event.


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A) Device in static field B) First event grounding in field

C) Device left with net charge D) Second event grounding in later step

Figure 4 - ESD by Induction

Machin e Model (MM)

Automated handling equipment can also develop a significant charge if the equipment and process arenot properly designed. When such equipment (for example, a robotic arm) touches a device, somecharge may be transferred, as in the HBM. However, here, the discharge is through a very lowresistance. This results in a faster, higher-current pulse. The equivalent circuit for the machine model is

similar to the HBM, except that the body resistance is lower and a series inductance should beincluded (since it will have a dramatic effect on the pulse). Experience with the proposed standardmodels has shown that the MM produces failure models similar to those seen in HBM testing.


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SOURCES OF ESD DAMAGE

The materials listed in the triboelectric series (Table A) are found in most environments. These materials areconstantly separated or rubbed together. For example, charges are generated by belts moving over rollers,

brushes rotating through solvents, and clothing rubbing against STYROFOAM

or other nonconductivesurfaces. Untreated STYROFOAM is more prone to retaining a charge than many other materials; therefore,it should never be used where electronic assemblies are susceptible. Integrated circuits and printed wiringboard (PWB) assemblies can easily be exposed to static charge when such nonconductive materials arepresent.

A person walking across the floor, sliding on a chair or contacting a work surface can generate thousands ofvolts of static electricity. Devices, even if assembled in circuit packs, can be exposed to damaging staticpotentials if allowed to shift inside containers. Static potentials that can be generated are affected by:humidity, rate of airflow, flooring, furniture, clothing, other materials, and differences among individuals.Table C - Typical Charge Generatorslists typical charge-generating materials.

Envi ronmental Condi t ions

Grounded conductive materials provide a path for electron flow that prevents a charge buildup. In a humidenvironment, moisture absorbed on the surface of any object will provide a similar leakage path, resulting inlow static potential. In dry conditions, such as a heated building in wintertime or in a naturally arid climate,the leakage rate no longer equals the rate of static generation, and large static potentials can result. Table B- Typical Electrostatic Voltages shows the effect of relative humidity on static generation. As relativehumidity increases from 10 to 55 percent, static potentials decrease dramatically (in one case by more thana factor of 10). Results of this type vary under different test conditions and with different materials. The effectof humidity is less for materials that do not absorb water, such as TEFLON.

Heating or drying operations remove conductive moisture from both the item and the ambient air, resulting ina greater tendency for materials to charge. The application of a nonconductive coating will increase thelikelihood of static charging. In a typical environment, higher speeds of moving machinery and conveyorshave increased the occurrences of material separation. When material separation is combined with the moreprevalent use of nonconductive and nonabsorbent materials, static electricity problems are increased.

Device Sensi t iv i ty

Many electronic components are sensitive to electrostatic discharge. The degree of sensitivity is determinedby the device circuit design and structure. Packaging can also affect sensitivity, particularly to the charged-device model.

All semiconductor devices including discrete transistors and diodes, optoelectronic devices (photodiodes,LEDs and lasers), and integrated circuits are sensitive to ESD. Other devices, such as SAW filters and thin-and thick-film resistors, may be sensitive. The fine-line designs of integrated circuits (both bipolar and MOS),with shallow junctions and thin insulators, are particularly vulnerable. While the particular technology used tobuild a device strongly influences its intrinsic sensitivity, the effective sensitivity is also a function of theattention paid to ESD protection by the device designer. The MOS circuits with unprotected gates may fail at20 volts. However, depending on performance criteria, varying degrees of protection may be built into thedevice. Protection circuit designs are available that can provide ESD withstand ratings of 8,000 volts (HBM)

and 3,000 volts (CM). Most semiconductor devices used in the electronics industry today vary to less than250 volts and up to 8, 000 volts (HBM), however high speed devices can be damaged by ESD events as lowas 40 volts. There is no consensus on wafer level ESD sensitivity, but there have been some documentedcases of ESD damage to wafers during integrated circuit fabrication.

Registered trademark of Dow Chemical Co.


52

Registered trademark of E. I. Du Pont de Nemours


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52

TABLE C

TYPICAL CHARGE GENERATORS

ITEM TYPE

Work SurfacesFORMICA*, Finished Wood, Synthetic Mats Underground Metal,Glass or Fiberglass

Chairs Fiberglass, vinyl, Other Plastics, Ungrounded Metal, Finished Wood

ClothingClean-Room Garments, Finger cots, Gloves, Wool, Synthetics,Shoes and Boots

Floors Carpeted, Vinyl, Waxed

Packaging MaterialsPolyethylene Bags, Bubble Pack Material, Foam, Packaging Pellets,Plastic Trays and Boxes

ManufacturingProcesses

Conveyors, Drive Belts, Machinery, Nylon Scrub Brushes,Nonconductive Liquids, High-Velocity Airflow, TemperatureChambers, Environmental Ovens, slides, Rails, TEFLON

* Registered trademark of FORMICA Corporation.

Table C - Typical Charge Generators

Table D is based on published values of ESD sensitivity for various technologies. It is important to note thatdevice technology is not a good indictor of ESD sensitivity. The growth of high-speed electronics andphotonics is increasing the number of devices with low ESD withstand voltages.

TABLE D (NOTE)

DEVICE SENSITIVITY

DEVICE TYPE

RANGE OF ESD SENSITIVITY

(VOLTS)MOSFET 100-200

GaAsFET 100-300EPROM 100-2,500

OP AMP 100-2,500CMOS 250-3,000

Schottky Diodes, TTL 300-2,500Film Resistors (Thick, Thin) 300-3,000

Bipolar Transistors 100-7,000

Photodiodes 100-1,000Note: Do not use this table as a source for device information. This table

is not comprehensive. It is intended to show ranges only.

Table D - Device Sensitivity


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Table E - HBMHuman Body Model

(Per ESD STM5.1-2001)

Class Voltage Range

Class 0 < 250 volts

Class 1A 250 volts to < 500 volts

Class 1B 500 volts to < 1000 volts

Class 1C 1000 volts to < 2000 volts

Class 2 2000 volts to < 4000 volts

Class 3A 4000 volts to < 8000 volts

Class 3B 8000 volts

Table F - CDMCharge Device Model

(Per ESD STM5.3.1-1999)

Class Voltage Range

Class C1


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Stat ic Shoc k

People are a prime source of device-damaging electrostatic potentials. Activities such as walkingor working at a bench can generate thousands of volts of static potential. When a charged personhandles a static-sensitive device, the component may be damaged by either a direct HBMdischarge or become charged and susceptible to a subsequent CDM event. A person cannot

feel static discharge until the potential approaches 3,000 volts; however, many commonlyused devices are subject to damage at less than 500 volts. See Table D - Device Sensitivity.

Note: "If an individual experiences a "felt static discharge" while working in or passing through anESD sensitive area, that is a prime indication that there are serious ESD control problems in thatarea and immediate corrective action must be implemented."

ESD in clean room s and i ts Effects on IC Wafers

Electrostatic potentials greater than 10 kilovolts are common in clean rooms because of thewidespread use of TEFLON and other clean room-compatible insulating plastics

1. Robotic wafer

handling equipment has been found to malfunction because of ESD between charged wafers andthe equipment. Simulated discharges of 8 kilovolts or more were required to replicate thesemalfunctions.

Although these discharges are evidently common in clean rooms, devices on wafers are thoughtto be less threatened by ESD than packaged devices for two reasons. First, the high conductivityof the wafer may help shield the devices from ESD induced currents. Second, the devices on thewafer are not connected to anything, so ESD currents are not channeled through the I/O circuitryof the integrated circuit as they are in a packaged device.

As a result, ESD protective measures have not been developed for clean rooms as much as theyhave for assembly facilities. However, when handled improperly, wafers are damaged by ESD

2.

Wafer damage can occur anywhere the ESD spark impinges on the wafer. Even finished waferscan be damaged, because multi-kilovolt electrostatic potentials exceed the breakdown strength ofthe wafers outermost CAPS (contact and protective seal) layer, enabling the ESD to burnthrough and damage underlying structures. Thus, ESD damage to wafers does not usually occurin I/O structures, which have designed-in ESD protection circuitry. Because of this damagesusceptibility, semiconductor wafers must be considered to be ESD sensitive.

Although wafers are sensitive to ESD, assessments of the overall effects of ESD on wafermanufacturing yield have not been reported. One reason for this is that ESD damage to wafers isobscured by other kinds of damage that wafers incur during manufacture. Device yield near theedge of wafers is often low because of mechanical damage to devices near the edge whenwafers are handled by tweezers; a practice that is being superseded by automated handlingequipment. When wafers are charged, the maximum electric field occurs at the edge. ESD wouldbe presumed to occur more frequently at the edge, where the wafer is usually first contacted. It ispossible that when improved handling practices reduce mechanical damage near the edges of

wafers, residual ESD damage will show up.

Although present wafer handling practices may coincidentally protect them against ESD damage,it is important to remember the wafers inherent ESD vulnerability in case these handlingpractices ever change. Areas of wafer containing devices should never be contacted unless both

1See Chemelli, R. g., et al, in Appendix C References.

ALCATEL-LUCENT ESD CONTROL HANDBOOK ISSUE 13 CLASSIFICATION= OPENPage 22 of 52

2See Turner, t., in Appendix C References.


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ESD CONTROL REQUIREMENTS AND TECHNIQUES

Int roduct ion

One approach to protecting against ESD damage is to design special protection features into

devices, circuit packs, and systems to withstand ESD. This section references minimumrequirements for both designed-in protection and handling techniques. Handling techniques areused to prevent static charge accumulation so that ESD does not occur. Both approaches arenecessary, but they have certain limitations and trade-offs that must be considered. The primarypurpose of this section is to define handling requirements and techniques that will control staticcharge accumulation.

Design ed-In Protect ion

The most efficient way to protect microelectronic circuit elements is to build protective circuitryinto the device during its manufacture. Protection diodes, field oxide transistors and resistors maybe built using the same process steps that produce the operational circuit elements. Protection

circuitry design is a trade-off among several factors, most notably device performance, devicemanufacturing constraints (that is, mask levels and material properties) and device handling (ESDcontrol). The protection circuit must respond to the ESD transient faster than the device beingprotected. Although significant device protection can be obtained by designed-in circuitry, nodevice manufacturer has been able to eliminate the problems of ESD damage. For this reason,additional protective handling measures are also needed.

Electronics technology trends are forcing devices to operate at considerably higher speeds.Sometimes, speed and other performance criteria may restrict the full use of available protectionstrategies. The need to use these limited protection schemes should be recognized andcommunicated early to the manufacturers and users of the devices, so that protection may bebuilt in at the circuit pack and system level and so that the need for special handling techniquesmay be anticipated. This is especially critical for ultra sensitive (Class 0, see Work AreaClassification) devices, since standard control procedures are not sufficient and the use of someautomated assembly techniques may not be allowed. Circuit pack level protection techniquesinclude shielding, conformal coating, special connector designs, guard rings and componentplacement.

The design of completed systems must also take into account disruptions caused by ESD.Corrective measures include shielding and circuit board layout considerations typical of noisesuppression techniques. The ESD sensitivity information is required in product design informationfor each new microelectronic device, circuit pack or system.

Basic Rules for ESD Control

A. Assume that all electronic (solid-state) components and assemblies are

sensitive to ESD damage.

B. Never touch a sensitive component or assembly unless properly grounded.

C. Never transport, store or handle sensitive components or assembliesexcept in a static-safe environment.

D. Require employees, suppliers and subcontractors to follow the three basicrules.



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Static-Safe

Static-safe conditions or materials provide adequate protection for the product sensitivity in theintended application. However, the ideal material often does not exist and it is virtually impossibleto prevent some degree of charging. Therefore, trade-offs are generally involved. Engineering

judgment is necessary to consider these trade-offs and to determine if a material condition is

static-safe.

A static-safe environment for electronic components and assemblies involves:

Controlling static buildup whenever possible.

Eliminating charges wherever they exist. How these charges are removed depends onwhether the charged object is a conductor or nonconductor.

Grounding all conductors, including people, in the workplace. Dissipative mats should beused on benches and/or floors. Operators should use ESD protection devices asindicated in ' 7.0- Personnel Grounding procedures, or follow local ESD Coordinatorinstructions. These steps will ensure that static potentials within the system remain atzero. Handling and grounding techniques, combined with an awareness program

designed to enlighten personnel about the hazards of ESD, are the most effectivemethods for eliminating ESD damage.

Ant ist at ic Property

This property refers to the prevention of triboelectric charge generation. It will effectively minimizethe production of a static charge when materials come in contact and are separated. Thisproperty is not a dependent function of material resistivity or of static decay performance. In otherwords, a material could be conductive or static-dissipative and not antistatic.

Static Conduc tors and Nonco nd uctors

Conductors such as metal or carbon-impregnated materials allow electrons to flow and caneliminate a charge when connected to ground. Nonconductors (STYROFOAM, plastics, clothing,etc.) will not allow a charge to flow. Therefore grounding an insulator is useless. Elimination ofnonconductors from the workplace is the best solution, but if this is not possible, direct contactmust be avoided between sensitive products and the nonconductors. Ionized air is the next bestsolution.

Surface Resist iv i ty

For steady current flowing along a surface, surface resistivity is defined as the ratio of the electricfield (volts/meter) to the surface current density (amps/meter). The unit of surface resistivity isohms per square, to emphasize that for a uniform current density surface resistivity equals the

ratio of the voltage drop across a square region of any size to the total current flowing through thespace. Two categories of surface resistivity characterize most ESD combative materials. Theseare:

Conductive (


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Conduct iv e Mater ials

Conductive materials may or may not be antistatic and are the quickest to dissipate charge. They areused to shield some highly sensitive products. However, they do offer an element of considerable riskof ESD damage based on the charged-device model. Therefore, always avoid contact between theconductors of a static-sensitive product and conductive surfaces. If this contact is a processrequirement, use every precaution to ensure that the product is not charged before contacting a

conductive surface, and that the conductive surface is grounded. When a charged product touches aconductive surface, the rapid discharge may result in ESD damage. Conductive packaging materials

e of higher costs, and few products require shielding for

henoxes could be lined with dissipative material on the inside whereductive on the outside for rapid charge dissipation or shielding.

ystem-level ESD considerations for design is contained in the Electromagnetic Compatibility Global

hus, the reset lead may have to be treated as if

ge in a sandwich bag near the PC! Any design capable of responding to 1-nanoseconde design techniques to afford an adequate level of immunity to these types

ithstand voltages have been reported for improperly calibrated equipment. Themethod and machine specifications in X-19435 are similar to MIL STD 883, Method 3015.7 and ESD

Association S5.1.

for shipment are generally not used becauseither handling or shipment.

Static-Diss ipative Materials

In general, static-dissipative materials are preferred to conductive materials because chargedissipation occurs at a safe rate neither too fast nor too slow. Both categories have application wproperly used. For example, tote bthey contact the product, but be con

System Level Test ing

SProduct Applications Guidelines, Best Current Practices, and design documentation, which iscontrolled by the various product management teams

Design information specific to ESD is mention throughout the Lucent ESD Handbook. However, manyof the EMC concepts in the document also apply to ESD in the following way: structures that makegood radiating antennas also make good receiving antennas. A 100 MHz clock lead would needproper design to make it not generate excessive radiated emissions or be susceptible to ESD. A resetlead that almost never changes state is generally not an emissions concern, but it can causeperational problems if ESD generates a false reset. To

it were a 100 MHz clock. Thus the set of ESD sensitive structures in a design include most of thetraditional EMC structures as well as additional ones.

An important point to be made in the area of system-level immunity to ESD is that meeting industrystandards is no guarantee of satisfactory operation in the field. One example of this is the radiatedhigh-frequency (above 1 GHz) noise generated by small ESD events between pocket change andother small pieces of metal. It will be years before any standard covers this form of ESD, but manytypes of electronic equipment has been shown to be adversely affected by it as equipment bandwidthhas increased. Recently, it was shown that a particular 100 MHz PC could be locked-up by jinglingpocket chanpulses must use microwavof events.

Device Test ing

The ESD sensitivity ratings are assigned to devices using standard HBM and CDM test methods.These methods are described in Specification X-19435 (see Appendix B). The data provided by thesemethods is the ESD withstand voltage. The ESD withstand voltage is the highest voltage that a givendevice can accept and still operate according to its own specification. It is important that the equipmentused to simulate the HBM and CDM pulses meet the requirements of X-19435. Variations as great as6:1 in reported w



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ESD CONTROL REQUIREMENTS SPECIFIED BY CLASS

Table G - ESD Control Requirements Specified by Classspecifies control requirements according

to the following classifications:

Class 0 areas contain devices with ESD thresholds ranging from 0 - 249 volts.

Class 1A areas range from 250 - 499 volts.

Class 1B areas range from 500 - 999volts.

Class 1C areas range from 1,000 - 1,999 volts.

Class 2 3A areas ranges from 2,000 7.999

Class 3B areas range from 8000 volts and up.

1.0 Work Area Classi f icat ion

Not all devices (and consequently, assemblies) are equally sensitive to ESD damage. Somerequire more protection than others. In a given area, the ESD withstand voltage of the mostsensitive component determines the type of protection required. Consequently, circuit packassemblies are to be classified according to the most sensitive component. Classifications shouldbe based on tested withstand-voltage data, per Specification X-19435 (see Appendix B). In theabsence of such data, classifications may be subjectively based on factory or field data. However,the use of estimated thresholds should be minimized.

The engineering organizationshalldetermine and document the classifications for a given workarea so that the correct preventive measures are specified.

The ESD classification shallbe documented and kept with accordance to records section 12locally or for each work area. It is preferred that the ESD classificationbe postedon the ESD safe

area signs. If the ESD safe area has a single classification, it can be put at the entrance to anESD safe area. If there are multiple Classes of ESD areas within an ESD safe area, the specificareas shallbe marked appropriately.

The following method should be used to determine the work area classification.

Method 1

Method 1 consists of reviewing the Bill of Material (BOM), and identifying theESD threshold voltage of the most sensitive ESD device. This method is usedprimarily during an assembly process, where the components are handledand/or exposed to a potential ESD event.

Note 5: Classifications should be based on tested ESD threshold voltagedata, per Specification X-19435.

Method 2

Method 2 consists of reviewing or obtaining the design classification of thefinished product. For example, a circuit pack in its finished state may havebeen designed (ESD protection circuitry) to withstand ESD voltages higherthan its assembled components.

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Method 3

If ESD Classification of a product is not known, it shallbe handled as Class 0product until determined by the local ESD Coordinator.

For measurements or changing of components on a Printed CircuitBoard (PCB) or PCB Assembly refer to the ESD Control Handbook

(Section 1, Work Area Classification) for techniques and precautions.

For exchanging boards in a system refer to the ESD ControlHandbook(Section 1, Work Area Classification) for handling and ESDGrounding requirements.

1.1 Documentat ion of Wo rk Area Classif icat ion

The ESD classification shall be documented locally for a facility, or for each work area. Example;an EMS may state that all areas handling ESD sensitive devices shall be established to meet theminimum withstand-stand voltage of the most sensitive component used in that facility.

1.2 Warning Signs

Standard warning signs such as ESD Protection Required in This Area shall be posted asnecessary. Local standards may specify the location and format of the sign.

https://scportal.lucent.com/pls/portal30/docs/FOLDER/DOC_CONTENTS/ALUESDHB.PDFhttps://scportal.lucent.com/pls/portal30/docs/FOLDER/DOC_CONTENTS/ALUESDHB.PDFhttps://scportal.lucent.com/pls/portal30/docs/FOLDER/DOC_CONTENTS/ALUESDHB.PDFhttps://scportal.lucent.com/pls/portal30/docs/FOLDER/DOC_CONTENTS/ALUESDHB.PDFhttps://scportal.lucent.com/pls/portal30/docs/FOLDER/DOC_CONTENTS/ALUESDHB.PDFhttps://scportal.lucent.com/pls/portal30/docs/FOLDER/DOC_CONTENTS/ALUESDHB.PDF


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TABLE G

ESD CONTROL REQUIREMENTS SPECIFIED BY CLASS

AREA CLASSIFICATION (NOTE 2)ITEM

0 1A 1B 1C 2 3A 3B

DEVICE SENSITIVITY (VOLTS)CONTROL REQUIREMENTS(NOTE 2) 0-249 250-499 500-999 1,000-1999 2,000-7999 NONE

> 80001.0 Work Area Classification R R R R R

2.0 Personnel Training Program R R R R R

3.0 Personnel Certification R R R R R

4.0 Auditing R R R R R

5.0 Statistical Process Control R R R R R

6.0* Production Equipment Certification R R R R R

7.0 Personnel Grounding R R R R R

8.0 Flooring, Floor Finishes and Mats R S S S S

9.0* Transporting Products R R R R R

9.1* Carts R R S S S

9.2* Static-Safe Packaging R R R R R9.2* Static-Safe Bags R R R R R

9.3* Static-Safe Tubes NP R R R R

9.3* Static-Safe Tote Boxes R R R R R

10.0* Static-Generating Material Control R R R R R

11.0* Dissipative Work Surfaces R R R S S

12.0* Dissipative Gold Finger Shunts R R R S S

13.0* Extraordinary Measures R S S S S

14.0 Other Controls S S S S S

15.0 Installation Standards R R R R R

NOTE 1: Control requirements are described in more detail on the following pages.

NOTE 2: R = Always required when used.S = Required when specified by Engineering.NP = Not Permitted for Class 0 CDM sensitive devices.

NOTE 3 Sections 8-13 (Flooring, floor finishes and Mats through Extraordinary Measures) are process-specific and may not apply to all applications.

* Applies to CDM ESD events.

See Section 9.2 for further explanation.

See Section 9.3 for further explanation

Table G - ESD Control Requirements Specified by Class



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2.0 Personnel Training Program

The success of ESD control programs depends on all personnel understanding ESD principles. Apersonnel training program is required for engineers, operators, installers, and managementpersonnel. It is the responsibility of Top Management or its delegates (e.g., ESD engineeringand/or training organization) to develop and implement the local ESD training program. ESD

bulletins are part of ESD training and shall be issued as necessary. The ESD Training programmay be provided in a classroom environment or as a web base course.

3.0 Personnel Cert i f icat ion

All Alcatel-Lucent employees who have contact with ESD-sensitive components and assembliesshall undergo an ESD Certification Training Program that leads to knowledge of properrequirements and handling techniques. This knowledge and behavior shall be tested by averifiable and valid testing method, which will be used to verify the accuracy of the employee'sESD safety knowledge.

Electronic Component Suppliers and EMS shall have established an ESD Certification Training

Program that is in compliance with a recognized industry standard or in accordance with theLucent ESD Handbook.

3.1 Re-cert i f ic at ion Interval

Re-certification is required Bi-annually (once every 2 years) with a 45-day grace period. Yourorganization may require re-certification more often.

4.0 Audi t ing

Within Alcatel-Lucent locations where ESD sensitive components are present, a system forauditing compliance to ESD procedures shall be established for all ESD sensitive areas. The

Alcatel-Lucent ESD Inspection Guide or equivalent procedures should be used as a reference forestablishing an auditing program. For locations, where an equivalent procedure has not beenestablished, the Lucent Management Systems document for ESD Auditing shall be utilized.

For 3rd

party audits of suppliers and EMS, the X-Spec 21381 shall be used.

5.0 Stat ist ical Process Contro l

Where appropriate, statistical process control techniques shall be applied to control the ESDprocess. Techniques such as control charts or trend charts may be used. Determining factors fordeciding the level of statistical process controls includes:

The type of work being performed (continuous assembly production verse laboratoryareas)

The level of compliance (work area classification)

The number of employees requiring ESD certification

The type of materials/products and the type of ESD monitoring equipment

5.1 Process Contro l Documentat ion



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A process control layout or equivalent shall be developed or adopted for local use. Theprocedures used and the frequencies applied may be established locally and may be based oneither manufacturing recommendations or experience. For instance, in a manufacturingenvironment, wrist straps and conductive footwear should be tested daily and tablemats shouldbe tested at least monthly.

5.2 Process Con trol Method s

The process control methods shall include both visual inspections and electrical tests to verifythat the ESD process complies with the Alcatel-Lucent Electrostatic Discharge Control Handbook.Root cause analysis, preventive corrective action, and corrective action shall be employed, asnecessary, to maintain compliance with ESD process requirements.

Procedures such as proper use of tote trays, the control of static-generating materials and propergrounding of personnel must be periodically inspected and the results recorded as required.Control products, such as wrist straps, heel straps, tote boxes, dissipative table mats, and ESDgrounds must be periodically tested for proper operation and the recorded as required

6.0 Produ ct ion Equ ipment Cert i ficat ion

The use of automated facilities makes the ESD qualifications of handling, test, and othermanufacturing equipment increasingly important. These facilities must be designed with twopurposes in mind. One is to prevent damage to the items being manufactured or handled. Theother consideration is to protect the facility from ESD damage or malfunction.

6.1 The ESD Acceptance Cri ter ia for Equipm ent and Faci l it ies

Associated wi th Manufactur ing, Handl ing and Test ing

Equipment

New facilities shall meet the criteria listed in the following paragraph, and older

facilities should, as necessary, be reviewed according to the same standards.Designers, suppliers, and/or purchasers of manufacturing equipment shouldcertify the designs to ensure that these qualifications are met.

The equipment shallbe qualified for ESD safe operation according to thefollowing requirements for final acceptance:

(1) All conductive and/or dissipative materialsmust be grounded,

(2) Any movementmustnot result in excessive triboelectric charging of printed wiringboards (PWB) or components,

(3) Surfaces that contact PWB or componentsmustbe static-dissipative or, as a last

resort, conductive,

(4) The facilityshallnot be subject to ESD damage or malfunction due to ESD,

(5) The facilityshallbe equipped with provisions for convenient wrist-strap groundingof personnel. The ground point shallbe identified, and

(6) Work surfacesshallbe covered with a grounded Alcatel-Lucent approved static-dissipative material.



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(7) ESD protective tools such as static bags mustbe made available.

7.0 Personnel Groun ding

Personnel are required to be properly grounded whenever they touch a sensitive component orassembly. Grounding is not required when sensitive items are in approved transportingcontainers (tote boxes, IC tubes, factory packaging, etc.). An assembly that has failed applicablesystem level tests or is untested is considered sensitive while in operation. In these instances, apersonnel grounding is required during operations such as system test.

7.1 Overal l Requ iremen ts

The method used for grounding personnel must include either a wrist strap and/or footwear.When seated, each operator must wear a wrist strap connected to a grounding system. Whenstanding, conductive footwear may be used with conductive or dissipative flooring and floorfinishes as an alternative. The grounding system (typically equipment ground) must be commonto all ESD control facilities (tabletops, chairs, floor mats and wrist straps), and be connected tocommon ground with 1 ohm resistance (See section 10 for more detail).

7.2 Wrist Straps

The sole purpose of wrist straps is to ground personnel. Tested and properly grounded wriststraps are the first line of defense against ESD damage. Typically, the standard ESD straps aremade of cloth, plastic or metal. These types of straps are flexible wristbands with minimum of a1-megohm resistor in the ground cords.

The wrist straps must contact the skin to be effective. Continuity from point of connection toground must always be maintained. ESD wrist straps and cords are to be considered a unit andmust be assigned to and used by one employee. The wrist strap/cord must be connected to a anESD constant monitor system or tested on each entry to an ESD Sensitive area Testing of thewrist strap assembly must be performed by the use of a calibrated wrist strap checker with results

of the test indicated in a logbook. If found defective the wrist strap/cord defective part must bereplaced and verified to function properly before entering the ESDS area. The owner of the wriststrap must report the defective finding to the local ESD coordinator. The coordinator willdetermine what appropriate steps will be taken to verify if any product was impacted by thedefective wrist strap from the time of the previous passing test. If necessary, the coordinator willprovide guidance for remediation of the situation.

When tested from the fingertip using an approved EOS/ESD Checker, wrist straps resistancemust measure within an acceptable range of 750 kilohms to 10 megohms.

In addition to the standard wrist straps, installation groups utilize Self-Testing ESD Wrist Strapssuch as the R-4987C. The self-checking wrist straps are only available through the InstallationOrganization (see Section 15.)

Note: At the release of the ESD Handbook, Alcatel-Lucent does not recognize the use ofWireless ESD Wrist Straps.

7.3 Footwear

Several Types of conductive footwear are available all of which must be used with conductive ordissipative flooring. Always wear conductive footwear on both feet and comply with local safetystandards.



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When tested using an approved EOS/ESD Checker, the footwear resistance must measurewithin an acceptable range of 750 kilohms to 10 megohms.

7.3.1 Heel/Toe Strap s

These devices are used to ground personnel at standing work positions. The typical heel

straps/toe straps are conductive straps that can be used with most types of shoes.Heel/toe straps may be used with steel floors if a minimum of 1 meg-ohm of resistance isprovided between the operator and ground. Always wear heel straps/toe straps onboth feet.

7.3.2 Boo t Straps

Bootstraps are alternatives to heel straps and can be worn on footwear that extend toohigh to accommodate the standard heel strap. They may also be used on conductive(steel) floors if the bootstraps are equipped with a minimum of a 1-megohm resistor.

7.3.3 Cond uct ive Boo ts

Conductive Boots are typically disposable, fit over street shoes, and contain a conductivestrip to ground the wearer. They are not recommended for use with steel floors unless theboots can be equipped with a minimum of 1 meg-ohm of resistance between the operatorand ground.

7.3.4 Conductive Shoes

Typical conductive shoes have conductive under-surfaces that electrically connect theusers feet to the walking surface through a minimum of 1 meg-ohm of resistance. Theyoffer a more permanent alternative to heel straps and boot straps.

7.4 Seated Wor k Pos it ion s (Benches, Test Sets, Etc.)

All personnel handling ESD Sensitive products/components must wear a properly operatinggrounded wrist strap while seated in both Non-ESD Safe and ESD Safe Chairs. Seated workpositions may consist of non-ESD safe, ESD safe chairs or in cases where there is a mix ofchairs the mandatory wrist strap requirement applies to both. The following process andequipment requirements shall apply for the use of chairs at work positions requiring ESDprotection measures.

7.4.1 non-ESD Safe Chairs

At seated work positions, both the work surface and the operator must be connected to a

common grounding system. The operator must wear a grounded wrist strap to beproperly grounded.

7.4.2 ESD Safe Chairs

At seated work positions, both the work surface and the operator mustbeconnected to a common grounding system. The operator mustwear agrounded wrist strap to be properly grounded. ESD Safe chairs can be usedto provide additional protection for classes that are more sensitive than Class



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0 and should be used when exceptional controls are necessary such as inhandling Class 0 devices for work positions equipped with ESD safe chairs:

(1) The ESD safe chair seats, backs, arms, bases with plastic covering, andposition work surfaces shallhave static dissipating characteristics with asurface resistance between 1x10

5and 10

10ohms at a relative humidity of

12% and 50%, and

(2) The ESD safe chair foot rests shallbe conductive with a maximum totalresistance from the chair footrest to chair ground of less than 1x10

4ohms.

7.5 Stand ing Work Posi t io ns (Packing , Mass Solder ing, Etc.)

ESD wrist straps mustbe used when directly handling ESDS materials/product(Direct handling refers to the handling of ESDS materials/product without theprotection of an ESD Bag, containers, or other approved protective media. Whenindirect handling (that is when a material/product is inside of a protected media)of ESDS materials/product is performed and wrist straps are a significant burdento the handler conductive footwear in conjunction with ESD safe flooring may be

used to provide tertiary ESD Protection. ESD Flooring, Finishes and matsforming an approved properly functioning ESD protective system. Class 0 Workareas mustbe equipped with flooring, carpeting, floor finishes, or mats that aredissipative or conductive. Engineering may require that ESD flooring be used forany ESD classification Class work areas. When specified for less sensitive areas,the same requirements for Class 0 flooring shallapply.

8.0 Floo r ing, Finishes, Carpet ing and Mats

8.1 Dissipat ive Floors/Floo r Finishes

The local ESD coordinatormust approve all flooring materials, and finishes.Approval includes:

(1) Approval of the selected dissipative materials,

(2) Verification that the material is performing to specified requirements, andAuditing procedures for measurements and maintenance of the floorreliability.

8.2 Floor Finish es/Carpeting

Floor finishes and carpeting are typically both dissipative and antistatic and are more forgivingbecause of antistatic properties (< 10

11ohms). Finishes shall be between 1x10

5and 10

11ohms.

Procedures can be found in the ANSI/ESDA S7.1 Standard at:;http://www.esda.org/standardlistings.html

8.3 Floor/Table Mats



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Conductive and dissipative floor mats are used primarily to ground personnel through conductivefootwear. Floor mats are used as an anti-fatigue measure and/or to provide a dissipative surfacewhere there is no dissipative floor or floor finish available. Resistivity shall be less than 10

7ohms

per square for ALL floor mats and resistivity for all table mats shall be between 1x105

and 1011

ohms.

9.0 Transp ort ing Produ cts

When ungrounded personnel transport products, the products must be transported in static-safecontainers that include but are not limited to those specified in Table G(tubes, reels, bags, boxes,etc.).

9.1 Carts

Carts must be metal, and product tote trays must be conductive or if plastic static dissipative andall types shall be grounded during the direct handling of sensitive product. Grounding shall beachieved by a ground cord (or an equivalent ground) while inserting or removing sensitive productfrom the cart or tote tray.

New carts purchased should be equipped with a common ground point, typically a banana jack.They should also be equipped with drag chains and/or conductive wheels when used inconjunction with ESD Safe flooring. They must also have, grounded dissipative surfaces andcomply with local standards. They should be designed so that there is no direct contact betweenthe conductive elements of the cart and the conductors of ESD sensitive product.

Older carts that are not equipped with a common ground point can still be used by grounding thetote trays individually during insertion and removal of ESD sensitive product. These carts shouldalso be equipped with drag chains such that 12 to 18 inches is in contact when used withconductive flooring.

NOTE: While not preferred, when used in conjunction with an EOS/ESD approved flooringsystem, drag chains are a substitute for ground cords. Ground cords (or equivalent) are

the preferred method for grounding for carts.

9.2 Static-Safe Packag ing

All products containing ESD sensitive devices must be shipped/received inESD -safe packaging that is marked with an industry-standard Static

Awareness Symbol. (See Figure below the lettering is black on a yellowbackground.) All packaging materials used for these items mustbe ESD safe.The static awareness label identifies contents that are ESD sensitive andrequire special handling precautions at the receiving end. ESD safe materialtest specifications are defined in EIA No 541, Packing Materials Standardsfor Protection of Electrostatic discharge Sensitive Devices, from theElectronic Industries Association. All packaging materials mustmeet one of

the following criteria: Use of Static Intercept packaging.

Initially qualified and periodically re-qualified based on local needs.

Verification from supplier of package adherence/certification and bedocumented.

If none of the above criteria are met, a waiver should be requested. A one-halfinch air gap is a recommended technique for providing shielding protection forESD sensitive devices or assemblies. Static-dissipative packaging dunnageoften provides adequate spacing.



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Figure 6 Static Awareness Symbol

It is strongly recommended that all incoming packaging of non- ESD sensitiveitems be both static-dissipative and antistatic and also meet the requirementsof 91NJ1045. Static-generating packaging materials often migrate to areaswith ESD sensitive items present, resulting in ESD damage. Additionally,administrative costs associated with managing these static-generatingmaterials have been significant and can be minimized with thisrecommendation.

It is required that for all new manufactured ESD sensitive products

primary packaging (Packaging that is in intimate contact with product)be in compliance with 91NJ1045, 800-001-009, and X21386.Packaging and transport bags are to be made of Static Interceptmaterials. Secondary packaging may be antistatic. Successfulapproaches for rigid containers include antistatic and static-dissipativematerials with sufficient air-gap between the packaging and product toprevent arc-through.

For BG/BDs or regions that follow other local procedures such as IEC61340, those standards shallbe referenced in local ESD Processdocumentation.

9.3 ESD Safe Trays , Tape and Reel, Tub es and To te Box es

Employees must load and unload sensitive products as determined by the area ESDclassification. In Class 0 and Class 1A areas, totes, Tape and Reel, or other containers, and carts(conductive or ESD safe) must be properly grounded when being loaded or unloaded. In Class 0,1A, 1B, and 1C areas, when unloading or loading metal trays, racks and other metal containersthat may contact the conductors of sensitive products, the containers must also be connected toground through an ESD safe surface or some other ground path.

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Tote boxes must meet the requirements of X-20938 (see Appendix B).

NOTE: Some Tape and reel packaging does not currently comply with packaging requirements(per X-20775, see Appendix B) and should not be used.

NOTE: Tubes are not permitted for Class 0 CDM sensitive devices. This is because most tubes

charge devices enough to jeopardize Class 0 CDM sensitive devices.

These requirements apply only when handling sensitive products directly. In other words, thecontainers may be transported or handled without grounding as long as personnel or equipmentdoes not contact the contents.

10.0 ESD Groun ding Requirements and Method s

To ensure that facilities, equipment, workstations, carts, shelves, ESD sensitive devices, andpersonnel are properly connected to a common grounding point, the following methods shallapply. The methods are in accordance with the recommendations of EOS/ESD standard ESD-S6.1.

Resistance Requirements

All ESD control points to common ground must be 1 Ohm.

Common ground to Building Auxiliary ground, AC equipment ground, Earth ground,or Vehicle common ground (Used for field service) must be 1 Ohm.

Exceptionso When the building uses an auxiliary ground there must be a resistance check

between the Building Auxiliary ground and the AC Equipment ground, thatresistance must be 25 Ohms.

o No common ground connection is allowed to an Isolated Ground. ThisIsolated ground is commonly exhibited by an Orange Electrical Receptacle,and when measured to the buildings AC Equipment ground the resistancewill be greater than the allowed 25 Ohms.

Method 1

Method 1 consists of grounding all of the workstations facilities, equipment, carts, shelves, worksurfaces, and personnel to the common ground, which is also referred to as the 'ESD commonpoint ground'. This type of grounding typically takes place through the use of the facility or earthground.

Method 2

Method 2 consists of grounding all of the workstations facilities, equipment, carts, shelves, worksurfaces, and personnel to the equipment ground which is connected to the earth electricalground connection (This connection is notthe neutral supply line). This is now the preferredground connection method because all electrical equipment at the workstation is already

connected to this ground. Connecting the ESD control materials or equipment to the equipmentground brings all components of the workstation to the same electrical potential.

Caution:If a soldering iron used to repair an ESDS item were connected to the electrical groundand the surface containing the ESDS item were connected to an auxiliary ground, a difference inelectrical potential could exist between the iron and the ESDS item. This difference in potentialcould cause damage to the item. Thus, any auxiliary grounds (water pipe, building frame, groundstake) present and used at the workstation must be bonded to the equipment ground to minimizedifferences in potential between the two grounds.



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11.0 Static-Generating Material Con trol

When ESD protection is required, all static-generating materials, such as plastics andSTYROFOAM, should be removed from the workplace. This is not always possible, however,since the materials may be an important part of an operation. For example, it would be virtually

impossible to eliminate such items as static-pro

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