anti static clean room flooring

Post on 15-Jul-2015

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ANTI STATIC CLEAN ROOM FLOORING ESD Flooring Issues In Clean Rooms

As electrostatic discharge (ESD) thresholds increase, awareness of ESD

standards and control in cleanrooms is a major concern.

ESD Floor

Most polymer flooring materials are electrical insulators,

which can create static buildup.

ESD Floor

Cleanroom floors are frequently found in

Electronics,

Pharmaceutical,

Biopharmaceutical,

Medical device industries,

Aerospace,

And other critical manufacturing environments.

Clean room flooring

Anti Static and Conductive floors are designed to measure at or below

35 Million ohms.

Clean room flooring

Typical contains from

500,000 to 1,000,000 particles

(0.5 microns or larger) per cubic foot of air.

Clean room flooring

A Class 100 cleanroom is designed to never allow

more than 100 particles (0.5 microns or larger)

per cubic foot of air.

Clean room flooring

Class 1000 and Class 10,000 cleanrooms are designed to limit particles to 1000 and

10,000 respectively

(In comparison, a human hair is about

75-100 microns in diameter).

Clean room flooring

A particle 200 times smaller (0.5 micron) than the human hair

can cause major disaster in a cleanroom !

Clean room flooring

Contamination can lead to expensive

downtime

and increased production costs.

Clean room flooring

In fact,

the billion dollar NASA Hubble Space Telescope was damaged and did not perform as designed because of a particle smaller than 0.5 microns.

Clean room flooring

ESA

is becoming more of a concern as static charges have been seen to actually bond contaminants to surfaces of products or tooling.

Clean room flooring

Example:

for a 4” wafer, charged to 1000 volts, a particle of 1 micron in diameter would have the bonding force of over 830,000 pounds per square inch.

Clean room flooring

Electrostatic attraction between charged objects and particles can be quite

strong compared to gravitational, aerodynamic, or

adhesion forces.

Clean room flooring

Conductive work surfaces can be considered a current-carrying

hazard to people

and ESD-sensitive devices.

Clean room flooring

ESD control measures traditionally have been required for:

• Defense, • Electronics assembly, • Wafer manufacturing, • Semiconductor, • & The disk drive industry.

Clean room flooring

In the area of ESA control, these industries have ramped up ESA programs

for their cleanrooms:

• Fiber optics, • Medical, • Pharmaceutical, • Wafer, • And disk drive manufacturing.

Clean room flooring

Controlling static electricity and ESD events in the cleanroom is important for these industries.

Clean room flooring

ESD S20.20 recommends a

target RH between 30% – 70%.

< 30% RH, materials have a greater tendency

to charge.

Surface Resistance versus Relative Humidity (RH):

THANK YOU

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