Teledyne Microscope & Magnifier GFC7000E Manuale Utente

Walking across nylon carpet 

1,500V 

35,000V 

Walking across vinyl tile 

250V 

12,000V 

Worker at bench 

100V 

6,000V 

Poly bag picked up from 
bench 

1,200V 20,000V 

Moving around in a chair 

padded with urethane foam 

1,500V 18,000V 

 

Damage to components occurs when these static charges come in 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 12-1 with the those shown in the Table 12-2, 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. 

MOSFET 10 

100 

VMOS 30 

1800 

NMOS 60 

100 

GaAsFET 60 

2000 

EPROM 100 

100 

JFET 140 

7000 

SAW 150 

500 

Op-AMP 190 

2500 

CMOS 200 

3000 

Schottky Diodes  300 

2500 

Film Resistors 

300 

3000 

This Film 
Resistors 

300 7000 

ECL 500  500 
SCR 500  1000 
Schottky TTL 

500 

2500