Guidelines For ESD Protection


Electrostatic Discharge

What is Static Electricity ?

Static electricity is an electrical charge at rest created mainly by friction and separation causing an imbalance of electrons. The magnitude of the static electricity depends greatly on the type of material, speed of separation, contact pressure, relative humidity of the environment, etc.

What is Electrostatic Discharge ( ESD ) ?

It is the sudden transfer ( discharge ) of static electricity from one object to another. It is a micropark.

What problems Static Charge have to all of us ?

In our daily activities, a person may feel shock if the electrostatic discharge is 3000 volts or more. However, modern electronic components such as IC chips cannot even withstand charges of less than 500 volts causing it to be damaged without noticing or realising the consequences. As technology is fast catching up, an electronic component becomes even more sensitive to the slightest amount of electrostatic discharge.

This have led us to realised how critical ESD is to us in our modern society causing many companies to invest substantially in such critical area to protect the sensitive components.


How Static Charge Is Generated ?


Triboelctrification is the charge that generated when two kind of material come into contact and then separated. These two objects became chaarged by gained electrons from the other. The magnitude and polarity of the chrages depends upon the characteristics of the two materials and affected by several factors like suface condition, size of contact aarea, speed of separation and humidity.

Field Induction

Static charge on an object create an electrostatic field that extend to surrounding can induce the charge on the object that place nearby and caused them to become charged. Once it come to contact to the ungrounded ESD sensitive devices, the amount of unbalance charges will immediately transfer which cause the device damaged permanently.

What Are The Solution To ESD ?

Virtually it is impossible to completely eliminate ESD in the production environment. We can minimise the problem by :-


This eliminates static charges in building up rapidly. Grounding drains all static charge bulits up instantly, making it the most common option used in the electronic industry. Grounding includes personnel grounding devices such as wrist strap and workstation grounding deviced such as ESD chair.


This method eliminates static charge through ionization. In this method, ions are created artificially to neutralise charges on both insulators and isolated conductors. However, neutralisation through ionization should go parallel with grounding as it only reduces the probability of an ESD event occuring.


Protect by isolating electronics components from charged objects, fields, and insulator transportation. Using the Faraday Cage concept, this concept emphasize that static charges cannot penetrate conductive material.


The best solution to an ESD problem is prevention and only you can prevent this from happening. The person in charge should be aware of event ESD could happen, undestand the application of ESD and ensure ESD DOES NOT happen. Training should be carried out to ensure everyone is knowledgeable of ESD awareness in ESD - sensitive areas followed by enforcement.

However, the ultiumate responsibility lies with everyone and this makes everything possible.

ESD Material Classification.

1. Conductive ( 10e3 - 10e4 ) - good shielding, allow charges to drains quickly, eliminate charges build-up.

2. Antistatic ( 10e5 - 10e11 )- Drains a charge to ground moderately, minimal shielding, minimizes charge build-up.

3. Insulative ( 10e12 - ) - unable to drain a charge to ground. Static charge bulidup remains on the insulators.

Static Electricity always exists

In today's workplace, the life and reliability of modern semiconductors require an environment where static electricity is continuously and totally drained to ground. Therefore, an Electrostatic Protected Area ( E.P.A ) must be established at all stages of receipt, storage, assmbly test and transport of electronic devices.



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