DC and RF Breakdown in Microscale Gaps From Near Vacuum to Atmospheric Pressures

The present work seeks to utilize plasma breakdown in GHz radiofrequency (RF) driven, large-Knudsen number, gaps to enable RF switches and limiters. As plasma breakdown in both regimes requires lower voltage than the classical Paschen curve predicts, we hope to achieve very low voltage RF switches. We report on the experimentally determined breakdown voltage vs. gap size at various pressures from atmospheric to vacuum (from small-to-large Knudsen numbers) for both DC- and RF-driven gold-electrode devices with gaps as small as 100nm. We present 3D simulations of the device operation using the Particle-In-Cell Direct Simulation Monte Carlo electromagnetic plasma code EMPIRE. The EMPIRE simulation model includes electron and ion-induced (Auger) Secondary Electron Emission, Fowler Nordheim field emission, ion-neutral interactions, electron-neutral interactions (elastic, excitation, ionization, attachment, and recombination), spontaneous emission, photoionization, and photoemission.