Dear MEMS folks:

Recent discussion in MEMS-talk about electrical breakdown criteria suggests
to me that there is a lack of awareness of the importance of field emission
in small gaps.  Some results of Wallash and others, who study esd damage
mechanisms in microelectronic devices, indicate that field emission, rather
than the more familiar Townsend avalanche process, dominates for gaps less
than a few microns.  The critical conclusion is that the apparent region of
"opportunity," where the Paschen curve swings upward below the minimum
sparking potential, may just not be useable in microdevices.

Those interested can click to the link below to download a short synopsis
concerning the "modified" Paschen curve.

        http://www.ece.rochester.edu/courses/ECE234/MEMS_ESD.pdf

Tom Jones


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Thomas B. Jones
Professor of Electrical Engineering
University of Rochester
P.O. Box 270126
Rochester, NY  14627-0126    (USA)
phone: 1-585-275-5233   fax: 1-585-273-4919
email: jones@ece.rochester.edu
http://www.ece.rochester.edu/~jones
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