Electronics Manufacturing ESD Control Fundamentals(Verison 2.0, 2017)

LEAN ESDTM Technology (Guangzhou) Co., Ltd.

Electronics Manufacturing ESD Control Fundamentals

Ver. 2.0 (2017)

Copper Hou (CTO)

iNARTE (US) Certified ESD Engineer (ESD-00583-NE)

ESDA (US) Registered Member (20160044)

LEAN ESD Technology Corporation Limited


Outline

Device Electrical Induced Failures

Device Electrical Failure Modes

Static Electricity and ESD

ESD Mechanism

How ESD Impact on Electronic Devices

Present ESD Event Types in Manufacturing

Device ESD Protection Strategies

Manufacturing ESD Control Approaches


Device Electrical Induced Failures

Catastrophic FailureDevices exhibit functional failures due to physical damage by

electrical stress, often detected with metal melting open, metal

melting short, PN junction breakdown, etc.

Parametric FailureDevices still functions well even if slight damage occurred due to

electrical stress, but one or more parameters exceeding the designed

control limit.

Latent FailureDevices do not exhibit functional and parametric failures after

stressed by electrical signals, however, usually found parametric or

functional failures at very earlier time during normal operations.

VCSEL LIV reliability test

MR head MRR

parametric changeNormal NG

Updated page


Device Electrical Failure Modes

Energy Failure Mode

The current flow through devices when

electrical signal stressed on energy

susceptible devices. Thermal failure

would occur upon the current reach to

the maximum withstanding level.

Voltage Failure Mode

Dielectric materials contained in voltage

susceptible devices would be broken

down when the voltage applied reach to

the maximum withstanding level.

Failure mode Analogy

ESDTR50.0-03-03

ESDTR50.0-03-03


Typical Device Electrical Failure Cases

Typical Device Energy Failures by ESD/EOS

Typical Device Voltage Failures by ESD/EOS

MOSFET IC RF IC

MCU IC

SAW Filter IC

TFT line of LCD panel

TFT line of LCD panel

Added page


Static Electricity and ESD

Static Electricity

Also referred to Electrostatic

Charge

Refer to electric charge at

rest.

ESD

Electro-Static Discharge

Refer to the spontaneous

electrostatic charge

transferring induced by an

electric field

There always exists electric

charges in the atmosphere,

named as Electro-Static charge.

Lighting is caused by numerous

electrostatic charges transferring in

a very short time, named as ESD.

VS


ESD Mechanism

ESD will not occur until both conditions met

The presence or accumulation of electrostatic charges

The available path for charge transferring

ESD Mechanism Formula

Q (Charge) + M (Transfer Path) = ESD

Either Q or M not met, ESD will not occur.


The Threats of ESD to Electronic Devices

ESD would typically produce either threat

Rapid (ns-us) and big discharge currents (usu. over 100mA)

Great potential difference (usu. over 50 V) across dielectric

material within device structure

Induce Energy Thermal Failures

Induce Voltage Breakdown Failures


How ESD Impact on Electronic Devices?

The ways ESD impact on electronic devices

Highly charged objects discharge to devices

Highly charged devices discharge to other objects at ground

or other different potentials

Devices exposed in high electrostatic fields may induce

voltage difference or current flow within device circuitry.

TFT-LCD:

Typical field

sensitive

Updated page


Present ESD Failure Types in Manufacturing

Charged Personnel discharge to Device/PCBA

Charged tools discharge to Device/PCBA

Charged Cable discharge to PCBA

Charged Device/PCBA discharge to grounded tools

HBM System level HBM

MM

CDM CBM

CDE


Device ESD Protection Strategies

Q (Charge) + M (Charge Transfer Path) = ESD

Strategy 1

Charge Generation/

Accumulation Control

1.Prefer to select low

charging materials

2.Eliminate/limit insulators

3.Use charge elimination/

neutralization

Strategy 2

Discharge Path

Control

1.Avoid non process

required contact with device

leads, eps. metal contacts

2.Always take static

dissipative surface for

Device intimate contact

Strategy 3

Device ESD Protection

1.Add built in ESD

protection circuitry

2.Take ESD protective

packaging for devices

during handling, storage or

transportation

Electrostatics CANNOT be avoided, but ESD damage CAN!

Updated page


Manufacturing ESD Control Approaches

Construct EPA for ESD sensitive

devices operations

Set up ESD protective

workstations for ESD sensitive

devices operations

Establish ESD grounding/

equipotential bonding for each

ESD workstation

Operator shall be grounded/

bonded for ESD sensitive

devices handlings

Eliminate/ limit insulators within

each ESD workstation

Prefer to use dissipative

materials for ESD sensitive

device intimate contact

Take ionization as secondary

option to eliminate/ control

charges

Take ESD protective

packaging for ESD sensitive

devices during handlings,

storage and transportation.

Take appropriate ESD caution

awareness for easy personnel

ESD control identification


Revision Change History

Version 1.0

First release in 2016.

Version 2.0

2nd updated release in 2017.

Added actual device failure cases of parametric and latent

failures;

Added the page of typical device energy and voltage failures;

Added typical field sensitive device, TFT of LCD panel;

Updated ESD protection strategy;

Added revision change history page.

Added page

Documents

Electronics Manufacturing ESD Control Fundamentals(Verison 2.0, 2017)