The ESD Association‘s Resistance-to-Ground (Rtg) requirement for an operator wearing a wrist strap is < 3.5 X 107 ohms (ANSI/ESD S20.20). A wireless wrist strap will never meet this requirement. Wireless wrist straps claim to work by “making (a) body’s static electricity to discharge through discharge box.” Assuming that an operator was tribocharged to 10…
Yes, the DoD formally adopted ANSI/S20.20-2014 on 4 June 2015. Please refer to the official announcement on the ESDA site HERE. For more information on recent changes made to S20.20, see the JAN/FEB edition of the ESDA’s Threshold – Significant Changes Made From the 2007 Version To The 2014 Version Of ANSI/ESD S20.20 To download a…
Read more Has the Department of Defense (DoD) adapted the ESD Association ANSI/S20.20-2014?
We are regularly asked if paper is OK in the ESD Protected Area or at an ESD workstation. Regular paper is insulative but tends to be low charging because it is hygroscopic (readily absorbs moisture). The primary concern with paper is placing ESD sensitive items on the paper interfering with the path-to-ground of the grounded ESD mat. Best practice…
ANSI/ESD S20.20 doesn’t mention hair, but the ESD Handbook ESD TR20.20 does. The general rule from ANSI/ESD S20.20 is in section 8.3. From ESD Handbook ESD TR20.20 mentions “human hair” is near the extreme end of the Triboelectric Series, so it can be high charging. But the above rule would apply; keep hair 12” away…
Read more Should dissipative hats be worn to protect ESD sensitive items from charges on hair?
Originally Published by InCompliance Magazine- September 2012 Now is the Time for ESD Control Programs to be Improved “Factory ESD control is expected to play an ever-increasing critical role as the industry is flooded with even more HBM (Human Body Model) and CDM (Charged Device Model) sensitive designs.” By Fred Tenzer and Gene Felder ElectroStatic Discharge…
Read more Now is the Time for ESD Control Programs to be Improved
Regular cleaning of an ionizer’s emitter pins is necessary to stay within the ionizer’s required limits of ANSI/ESD S20.20. If the ionizer has a filter, it should be cleaned at this time as well. One S20.20 required limit for ionizers is Offset Voltage of less than + or – 50 volts (this is often referred…
HUMAN BODY MODEL The updated standard ANSI/ESDA/JEDEC JS-001-2011, For Electrostatic Discharge Sensitivity Testing Human Body Model (HBM) – Component Level Table 3 has divided the Class 0 classification into two withstand voltage levels with class 0A being less than 125 volt sensitivity, and class 0B being 125 to less than 250 volts. If handling class…
Seeing ElectroStatic Discharge (ESD) damage is basically impossible. Damage to semiconductor device structure is NOT visible at ordinary magnifications of an optical microscope. If the microscope is capable of 1000X-1500X magnifications, you just might be able to “see” something. The method used, only occasionally as there is considerable expense, is by delayering and etch enhancement…
Most people do not start feeling the effect of an ESD event until the discharge is at least 2000 volts. It typically takes a ESD discharge of greater than 2,000 or 3,000 volts for a person to feel the “zap”. The number varies because the sensitivity of people is different and measuring the voltage is imprecise, so…
A Faraday cage or Faraday shield is an enclosure formed by conducting material or by a mesh of such material. Such an enclosure blocks external static and non-static electric fields. Faraday cages are named after the English scientist Michael Faraday, who invented them in 1836. An impressive demonstration of the Faraday cage effect is that…