Q: In our organization, there is a lot of paperwork that accompanies the product. Is this harmful to the product due to static generation? I have measured all the documents surface resistivity and find it to be dissipative in nature. Our production environment humidity is controlled from 40%-60%. I also tried to tribocharge the paper but there is no static voltage generated. The funny thing is when I rub my plastic comb and put it near bits of small paper, the bits get attracted to the comb. So is paper really harmful to the semiconductor products that we manufacture for our customer?
A: Hello. It’s good for you to observe the possible generators of static in an EPA (Electrostatic Discharge Protected Area) and to remove all non-essential insulators and to ground conductors or soft ground them, as the case may be, and to use neutralization on isolated conductors and essential insulators (ionization). You may notice low static charge potential or voltage on that paper, but what happens when it tribocharges with other materials in the EPA?
If you feel the paper is in the Static Dissipative range and you’ve got it sitting on an ESD bench mat, there should be no worries. If the paper has a surface resistivity of 1.0E9 Ω at your nominal humidity or less, all the better. If it’s above 1.0E11 Ω , it may or may not dissipate a big enough charge quickly enough… It’s sort of a risk. If you’d be interested in a more conductive ESD paper, we offer the SDP-8.5×11-W. This product is not humidity dependent. Having humidity is great at 30-50% range is helpful to get the best result. The Static Dissipative paper will still be below 1.0E10 Ω with humidity as low as 20%.
The next product that is helpful is the Document Protector which can be used on drawings, instructions, ECNs ECOs etc. that would be needed in the Production Area; we provide the DP-8.5×11 which is also Static Dissipative. The product is designed to be less than 1.0E11 Ω which is considered Static Dissipative for packaging and similar materials and it’s also said to be low charging or resistive of tribocharge. The static decay meets the specs for environments involving sensitive electronics and would be considered low-charging as well.
So you have decisions to make. You may be safe with what you’ve got, but if you’d like to be safer and more robust to lower humidity, you may consider the products above. If you’re ever in doubt, keep the documents at least 12” from sensitive electronics.
I hope this was helpful information to you. Please contact Alan for pricing and availability. Thank you for contacting us.