Experimental and theoretical studies of the breakdown voltage characteristics at micrometre separations in air

This paper presents experimental results and computer simulation for the direct current (DC) breakdown voltages in dry, synthetic and ambient air and discharge gaps ranging from 1 to 100 μm. The measured breakdown voltage curves were systematically analyzed and the effective electron yields from cathode for dry and synthetic air as a function of the reduced electric field have been estimated. As complement to the experimental results, simulations have been performed using a kinetic particle-in-cell (PIC) code. For the electrode gaps less than 20 μm, both experimental and simulation results revealed an interesting departures from the Paschen law on the left-hand side of the Paschen curve. The present results should be useful for the determination of minimum ignition voltages in microplasma sources as well as the maximum safe operating voltages and critical dimensions in other microdevices, high-power switches and circuit breakers.