1. ESD Control Experts
Electrical Overstress (EOS) and Electrostatic Discharge (ESD) Event
StaticControl.com
© 2015 Desco Industries Inc.

2. Agenda
EOS/ESD Basics
EOS/ESD Instrumentation
Applications

3. EOS/ESD Basics

4. EOS
ESD
Fig 3: ESD damage/short between Emitter/Collector regions on a device.
Fig 2: Transistor failure caused by electrical overstress damage across the die

5. Electrical Overstress (EOS)
Induced Voltage
EMI
EOS
Static Field
ESD
EMF
E-Field
H-Field
RFT
Surge
RFI
Note – EOS will be influenced by all signals
© 3M All Rights Reserved.

6. Important Terms EOS: Electrical Overstress
Static Field: Electrostatic Field
Induced Voltage: Voltage induced into the board or component by contact
ESD: Electrostatic Discharge
EMI: Electromagnetic Interference
EMF: Electromagnetic Field
E-Field: Electric Field
RFI: Radio Frequency Interference
EFT: Electronics Fast Transients
H-Field: Magnetic Field
Surge: A sudden, sharp increase of electric current or voltage in a circuit

7. What is Electrical Overstress (EOS)?
EOS (Electrical Overstress) is the exposure of a component or PCB board to a current or voltage beyond its maximum ratings. This exposure may or may not result in a catastrophic failure.
Fig 4: EOS on a damaged RS232C transceiver

8. How is Static Generated?- - - - - - - + + + + + + +
Contact and Separation of Materials
When two materials touch and then separate, electrons are stripped off of one material and transferred to the other. One material assumes an excess of electrons (or a negative charge), the other material assumes a positive charge because of the electron deficiency.
The exception to this rule is if both materials are conductive AND both are grounded: then there will be no excess or deficiency of electrons on either material.
© 3M All Rights Reserved.

9. What is Induced Voltage?
Refers to voltage being induced into the board or component by contact, resulting in current transfer through the component or board.
Fig 5: Current flow resulting from Induced Voltage

10. What is Electrostatic Discharge (ESD)?
ESD is a rapid, spontaneous transfer of electrostatic charge induced by a high electrostatic field through a spark between two bodies at different electrostatic potentials as they approach or are separated from one another.
There are three different ESD models identified by the standards presently:
Charge Device Model (CDM)
Machine Model (MM)
Human Body Model (HBM)
Fig 6: ESD damage to a bi-polar transistor

11. What is Electromagnetic Interference (EMI)?
Electromagnetic Interference is a disturbance that affects an electrical circuit, due to either electromagnetic induction or electromagnetic radiation emitted from an external source.
Fig 7: Electromagnetic Interference

12. What is Electromagnetic Field (EMF)?
Electromagnetic Field is a physical field produced by electrically charged objects. It affects the behavior of charged objects in the vicinity of the field. The electromagnetic field extends indefinitely throughout space.
Fig 8: Electromagnetic Field from a Cell Phone

13. What is Electric Field (E-Field)?
Electric field surrounds electrically charged particles.  Electric field exerts a force on other electrically charged objects.
Fig 9: Electric Field from positive and negative charge

14. What is Radio Frequency Interference (RFI)?
Radio Frequency Interference (RFI) refers to the noise caused by other Radio Frequency that interferes with information being transmitted.
Fig 10: TDMA mobile phone caused false readings in sensor of magnetic head tester and finally caused error message after failing several good GMR heads

15. What is Electrical Fast Transient (EFT)?
An Electrical Fast Transient event is a short-lived burst of energy in a system caused by a sudden change of state. The source of the transient energy may be an internal event or a nearby event.
Fig11: Single and bursts of EFT

16. What is a Magnetic Field (H-Field)?
A magnetic field is a field of force produced by moving electric charges.  Electric and magnetic fields are two interrelated aspects of a single object, called the electromagnetic field.
Fig12: Magnetic Field penetrating a superconductor

17. What is a Power Surge?
A Power Surge is an unexpected, temporary, uncontrolled increase in current or voltage in an electrical circuit. Heavy electrical equipment being cycled on/off is the most common cause of power surge.
Fig 13: Power Surge and its effect

18. SCS Products Used for Each Parameter
EOS: SCS Iron Man Plus Workstation Monitor
Static Field: SCS Air Ionizer Tester/Field Meter and Charger 718 or SCS EM Aware TNG ESD Event Monitor
Induced Voltage: (from ground) SCS Ground Pro Ground Integrity Meter, SCS Ground Master, and (by contact) SCS Charge Analyzer/Charge Monitor 711
ESD: EM Aware TNG ESD Event Monitor, SCS EM Eye Meter, SCS ESD Pro Event Indicator
EMI: EM Eye Meter
EMF: EM Eye Meter
E-Field: EM Eye, ScanEM-C
RFI: EM Eye Meter
EFT: EM Aware TNG ESD Event Monitor, EM Eye Meter
H-Field: ScanEM-C

19. What Constitutes a Safe EOS/ESD Environment?
The ultimate goal of an EOS/ESD program is to minimize EOS/ESD exposure to components and its influence on the process.
Without closed-loop control, the success of an EOS/ESD program is always uncertain.
Most current ESD controls are centered on performance of individual components of ESD protection, such as grounding, ionizers, materials, etc.
If EOS/ESD occurred in your environment, performance of individual protection components is lacking.
AN EOS/ESD Program is Only As Strong as its Weakest Link... It Is Imperative to Address All Potential Areas of Damage

20. What Constitutes a Safe EOS/ESD Environment?
The Most Ionizers
A Safe EOS/ESD Environment is One Where There is No EOS/ESD Exposure to Sensitive Environments. This Requires a Holistic Approach. +
The Best Ground +
Everyone Wearing Wrist Straps +
Compliance with ESD Standards
It is Important to Address Each Component of EOS/ESD Control… It is Equally Important to Monitor Your EOS/ESD Environment

21. EOS/ESD Instrumentation: Managing Your EOS/ESD Environment by Results

22. Detecting EOS/ESD Events in Your Production
Identify and measure EOS and ESD
Instrumentation helps ensures compliance
Products used:
SCS Iron Man Plus Workstation Monitor
SCS EM Aware TNG ESD Event Monitor Starter Kit
SCS EM Eye Meter
SCS ESD Pro Event Indicator

23. SCS Iron Man™ Plus Workstation Monitor
Monitors:
Electrical Overstress on the grounded board
Dissipative Ground (bench mat)
Operator Resistance and Body Voltage
Advantages:
Ensures compliance with EOS levels
Operator Body Voltage measurement
10^9 Mat resistance measurement
Small and easy to use

24. SCS EM Aware TNG ESD Event Monitor
Monitors:
Electrostatic Discharge (ESD)
Static Field or Ionization Balance
Ionization Decay
Advantages:
Measures all parameters through one antenna
Rejects non-ESD EMI events
LCD display for easy local viewing
MODBUS or 4-20mA output to FMS
Software available for characterization of ESD Events
Small footprint and Joystick for ease of use
Used for continuous monitoring of ESD, Static Field and Ionization Decay of production environment

25. 3M™ EM Aware TNG ESD Event Monitor Starter Kit
Diagnostic/Audit Tool:
ESD
Static Field or Ionization Balance
Ionization Decay
Advantages:
Measures multiple points (up to 6 units)
Complete with data acquisition and software for recording
Used as ESD diagnostic tool for different applications
Supplies factual data during Diagnostic and ESD Audit

26. ESD Audit: Going by the Facts
ESD Audit Report
Assumptions
Wrist straps 
Ground 
Ionizers 
Dissipative floors 
Dissipative garments 
Static voltage levels 
Gloves 
Tweezers 
Packaging 
Shelving 
ESD Audit Report
Facts
12 ESD Events stronger than 200V CDM observed at tool # 5 during 8 hrs. shift
Maximum strength of ESD Event was 550V CDM
ESD Events were correlated with new materials arrival and handling
Correction and verification to follow immediately

27. SCS EM Eye Meter Measuring Instrument: Advantages:
Electrostatic Discharge (ESD) – CDM, HBM, MM
Electromagnetic Field (EMF)
RF Signal
Advantages:
Portable, light weight, touch screen
Open platform – use specific sensor for specific parameter.
Used as ESD diagnostic instrument
Rejects non-ESD EMI events
Supplies factual data during ESD Audit
Uses directional antenna or remote antenna
Supplied with Calibration Certificate

28. SCS ESD Pro ESD Event Indicator
Diagnostic Tool:
Electrostatic Discharge (ESD)
Advantages:
ESD Indicator
Displays strength of ESD Event
Used as ESD diagnostic tool for different application
Supplies factual data during ESD Audit
Portable and easy to use
Rejects non-ESD EMI events

29. Identifying Root Causes At the Application Level

30. Finding the Root Causes of EOS/ESD
Identify the Application Where EOS/ESD Events are Being Created
For Example…
SMT Line
Soldering
Printer
Repair
Functional Test (Manual or Automatic Testing)
Manual Applications
Must Know Where to Look… 3M Expertise and Technology Can Help

31. EMI influence on EOS Common Mode and Differential mode signals
Powerful Linear Servo-Motors used to move feeders or robotic arms on an Automated tool
No filter
I=1.562A
Servo Filter
I=0.0069A

32. IC Handlers Discharges Happen When:
IC is picked up from the input tray
IC is placed in the input shuttle
IC is placed in the test socket
IC is lifted from the test socket
IC is placed in the exit shuttle
IC is placed in the output tray

33. Pick and Place Discharges Happen When:
IC is picked up from the tape and reel
IC is picked up from the tray
IC is placed on the board

34. Mechanism of EOS/ESD Damage in Handlers or Pick & Place
This Scenario Covers the Discharge Resulting from the Tribocharging of Encapsulation of the IC

35. Soldering and Soldering Extract
CDM or CBE Discharges Happen When:
Board travels and touches a grounded soldering wave
Soldering tip touches the component or the board
Solder touches the board
Component separation from board during extract application

36. Data Received from Wire Bonding
Wire Bonder ESD pattern with the same spacing during production.
Dual ESD Event other then Wire Bonder pattern during production.

37. Data Received from Multitester
ESD Events Detected At:
Multitest #6 Dispenser
Multitest #6 Q-Test
The lowest ESD Event detected on channel 1 was 38V CDM and the highest ESD Event detected on channel 1 was >500VCDM
The lowest ESD Event detected on channel 3 was 19V CDM and the highest ESD Event detected on channel 3 was 240VCDM
Static Voltage is higher at the Q-Test area
Static Voltage at the dispenser area is normally low with the exception when parts are put in the dispenser
When operator is not testing the chips
no ESD Events are detected in the area

38. Safe EOS/ESD Environment Based on Results
All EOS/ESD Protective Measures are Designed to Prevent EOS/ESD Events
By Managing EOS/ESD by Protective Measures, You ASSUME that Your EOS/ESD Problems are Solved
By Monitoring Your Environment and Managing EOS/ESD by End Results, You KNOW that EOS/ESD Problems are Solved

39. SCS Products & Services: Putting it All Together
Instrumentation for monitoring and detection of ESD/EOS events
Workstation Products for prevention of ESD/EOS events during mfg
Bags for prevention of ESD/EOS events during transit
Services
Step 1: Audit/Assessment of facilities by certified SCS ESD/EOS expert
Step 2: Detailed in-person training for your ESD managers and coordinators
Step 3: High-level training for operators and managers
Step 4: Continuous monitoring and support by SCS ESD/EOS experts
SCS is Not Just a Supplier, but a Collaborator… …And Your Competitive Advantage