How Electro-Static Charges Cause Damage; Table 13-1: Static Generation Voltages For Typical Activities; Table 13-2: Sensitivity Of Electronic Devices To Damage By Esd - Teledyne T802 Operation Manual

A Primer on Electro-Static Discharge

13.2. HOW ELECTRO-STATIC CHARGES CAUSE DAMAGE

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Teledyne API T802 Paramagnetic O
Table 13-1: Static Generation Voltages for Typical Activities
MEANS OF GENERATION
Walking across nylon carpet
Walking across vinyl tile
Worker at bench
Poly bag picked up from bench
Moving around in a chair padded
with urethane foam
Damage to components occurs when these static charges come into contact with
an electronic device. Current flows as the charge moves along the conductive
circuitry of the device and the typically very high voltage levels of the charge
overheat the delicate traces of the integrated circuits, melting them or even
vaporizing parts of them. When examined by microscope the damage caused by
electro-static discharge looks a lot like tiny bomb craters littered across the
landscape of the component's circuitry.
A quick comparison of the values in Table 13-1 with the those shown in Table
13-2, listing device susceptibility levels, shows why Semiconductor Reliability
News estimates that approximately 60% of device failures are the result of
damage due to electro-static discharge.
Table 13-2: Sensitivity of Electronic Devices to Damage by ESD
DEVICE
MOSFET
VMOS
NMOS
GaAsFET
EPROM
JFET
SAW
Op-AMP
CMOS
Schottky Diodes
Film Resistors
This Film Resistors
ECL
SCR
Schottky TTL
Potentially damaging electro-static discharges can occur:
65-90% RH
1,500V
250V
100V
1,200V
1,500V
DAMAGE SUSCEPTIBILITY VOLTAGE
RANGE
DAMAGE BEGINS CATASTROPHIC
OCCURRING AT
10
30
60
60
100
140
150
190
200
300
300
300
500
500
500
Analyzer Operation Manual
2
10-25% RH
35,000V
12,000V
6,000V
20,000V
18,000V
DAMAGE AT
100
1800
100
2000
100
7000
500
2500
3000
2500
3000
7000
500
1000
2500
07275B DCN6418