Primer on | Teledyne API Ultrafine Particle Monitor - Model 651 |
If one of the surfaces is a poor conductor or even a good conductor that is not grounded, the resulting positive or negative charge cannot bleed off and becomes trapped in place, or static. The most common example of triboelectric charging happens when someone wearing leather or rubber soled shoes walks across a nylon carpet or linoleum tiled floor. With each step, electrons change places and the resulting
Table 10-1 Static Generation Voltages for Typical Activities
MEANS OF GENERATION |
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Walking across nylon carpet | 1,500V | 35,000V | |
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Walking across vinyl tile | 250V | 12,000V | |
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Worker at bench | 100V | 6,000V | |
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Poly bag picked up from bench | 1,200V | 20,000V | |
Moving around in a chair padded | 1,500V | 18,000V | |
with urethane foam | |||
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H o w E l e c t r o - S t a t i c C h a r g e s C a u s e D a m a g e
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
A quick comparison of the values in Table 15 1 with the those shown in the Table 15 2, listing device susceptibility levels, shows why Semiconductor Reliability News estimates that approximately 60% of device failures are the result of damage due to
92 | 07506C DCN6727 |
