About Us
Introduction to ESD
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How static charge is generated
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How static electrostatic devices
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How to prevent ESD damage
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How to protect ESD sensitive devices
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HOW STATIC CHARGE IS GENERATED
Triboelectric Effect.
Field induction.
:: TRIBOELECTRIC ::
is the charges that generated when two kind of materials come into contact and then separated. Two objects become charged by gained electrons from the other, the magnitude and polarity of the charges depends upon the characteristics to those two kind of materials and affected by several factors like surface condition, size of contract area, speed of separation and humidity. (See Triboelectric series)
Once the charged that have been build up on the objects can be accumulated and then discharged through the ESD sensitive devices when it become to contract to the Charged objected.
:: FIELD INDUCTION ::
most of high voltages equipments like Computer Monitors, CRT oscilloscope that always generate of high intensity of electronic field, the Strong E Field that extend to surrounding can induce the charge on the objects that place nearby and caused them to become charged.
Once it come to contact to the ESD senilities, devices, the amount of unbalance charges will immediately through the devices to ground, that so call ESD damage by induction.
Field induction.
:: TRIBOELECTRIC ::
is the charges that generated when two kind of materials come into contact and then separated. Two objects become charged by gained electrons from the other, the magnitude and polarity of the charges depends upon the characteristics to those two kind of materials and affected by several factors like surface condition, size of contract area, speed of separation and humidity. (See Triboelectric series)
Once the charged that have been build up on the objects can be accumulated and then discharged through the ESD sensitive devices when it become to contract to the Charged objected.
:: FIELD INDUCTION ::
most of high voltages equipments like Computer Monitors, CRT oscilloscope that always generate of high intensity of electronic field, the Strong E Field that extend to surrounding can induce the charge on the objects that place nearby and caused them to become charged.
Once it come to contact to the ESD senilities, devices, the amount of unbalance charges will immediately through the devices to ground, that so call ESD damage by induction.
HOW STATIC ELECTROSTATIC SENSITIVE DEVICES HISTORY
INTEGRATED CIRUIT MR HEAD
The recently technology such submicron technology IC fabrication, Magneto Resistive Head all fabricated with very thin of insulative layer and metallic elements in few angstrom thickness, So all of these devices will become highly ESD sensitive devices, The thin insulation can be rupture and thin metallic or silicon element can be melt and caused short circuit by very low static potential, Some can not be withstand in 5 volts static potentials environment (Potential different) Such as MR Head, Giant MR Head technology etc.
VACUUM TUBE
MONOLITHIC HEAD |
BIPOLAR TRANSISTOR
COMPOSITE HEAD |
MOSFET
THINFILM HEAD |
HOW TO PREVENT ESD DAMAGE
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ESD Awareness Training program.
Reduce Risk of static charges generation build the ESD Safe work station, eliminate all non ESD Safe Packaging (Plastic, insulative Materials), Use conductive or dissipative flooring, Dissipative table top, ionization will be the other solution but need very good maintenance otherwise it will be very dangerouse. Grounding all conductive path are necessary, to provide Zero potentials environment. |
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HOW TO PROTECT ESD SENSITIVE DEVICES
Use protective material with FARADAY CAGE Shielding effect during storage and transportation (Conductive Bag, Sheilding Bag, Conductive IC Table, Conductive Container, Conductive IC Foams).
ESD Material Classification
The materials classified by Surface Resistivity (ASTM D257)
Surface Resistivity Range
ESD Material Classification
The materials classified by Surface Resistivity (ASTM D257)
Surface Resistivity Range
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1. Conductive - good shielding, allows charges to drain quickly, eliminates charges buildup.
2. Static Dissipative - drains a charge to ground moderately, minimal shielding, minimizes charge buildup.
3. Antistatic - minimizes charge buildup up via triboelectricity.
ESD Sensitive Device Classification
Class 1 0 v to 1,000 v MR Head, MOSFET, Thinfilm Head, Thinfilm Resistor, VMOS
Class 2 1,000 v to 4,000 v Protected MOSFET & IC, Schottky Diodes, OP Amp.
Class 3 4,000 v to 15,000 v Silicon Transistor, Bipolar IC, Power TR, SCR, Piezoelectric Crystals
The recently magnetic recording head like MR and giant MR Head Technology have been considered as the most ESD sensitive devices, it can be blow out when exposured to less than 10 volt potential different environment so, all concern material being use must be sellected to prevent tribocharge at very low level (production equipment, room facilities, packing, storage and transportation material)
2. Static Dissipative - drains a charge to ground moderately, minimal shielding, minimizes charge buildup.
3. Antistatic - minimizes charge buildup up via triboelectricity.
ESD Sensitive Device Classification
Class 1 0 v to 1,000 v MR Head, MOSFET, Thinfilm Head, Thinfilm Resistor, VMOS
Class 2 1,000 v to 4,000 v Protected MOSFET & IC, Schottky Diodes, OP Amp.
Class 3 4,000 v to 15,000 v Silicon Transistor, Bipolar IC, Power TR, SCR, Piezoelectric Crystals
The recently magnetic recording head like MR and giant MR Head Technology have been considered as the most ESD sensitive devices, it can be blow out when exposured to less than 10 volt potential different environment so, all concern material being use must be sellected to prevent tribocharge at very low level (production equipment, room facilities, packing, storage and transportation material)