How Electro-Static Charges Cause Damage; Table 9-1: Static Generation Voltages For Typical Activities; Table 9-2: Sensitivity Of Electronic Devices To Damage By Esd - Teledyne T360 Operation Manual

A Primer on Electro-Static Discharge

Table 9-1: Static Generation Voltages for Typical Activities

9.2. HOW ELECTRO-STATIC CHARGES CAUSE DAMAGE

Table 9-2: Sensitivity of Electronic Devices to Damage by ESD

264
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 9-1 with the those shown in the Table
9-2, 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.
DAMAGE SUSCEPTIBILITY VOLTAGE
DEVICE
DAMAGE BEGINS
OCCURRING AT
MOSFET 10
VMOS 30
NMOS 60
GaAsFET 60
EPROM 100
JFET 140
SAW 150
Op-AMP 190
CMOS 200
Schottky Diodes 300
Film Resistors 300
This Film Resistors 300
ECL 500
SCR 500
Schottky TTL 500
Teledyne API Model T360/T360M Operation Manual
65-90% RH 10-25% RH
1,500V 35,000V
250V 12,000V
100V
1,200V 20,000V
1,500V 18,000V
RANGE
CATASTROPHIC
DAMAGE AT
100
1800
100
2000
100
7000
500
2500
3000
2500
3000
7000
500
1000
2500
6,000V
07272B DCN6552