Actually at these small gaps, I believe the breakdown tends to follow the Paschen curves (http://en.wikipedia.org/wiki/Paschen%27s_law). We've been able to apply a few hundred volts across 2 micron gaps without arcing in our MEMS mirrors -- though we typically don't use such high voltages. Felix On Jun 28, 2010, at 4:42 PM, Gareth Jenkins wrote: > I also have no experience of such setups but if you are dropping a > voltage across a 20micron air gap, given the breakdown voltage of air > is 30kV/cm, you'll only be able to apply 60V before breakdown. > Maybe you can try it in a vacuum? > > Gareth Felix Lu felix_lu@yahoo.com