Microdischarge devices with 10 or 30 μm square silicon cathode cavities:: pd scaling and production of the XeO excimer

Silicon microplasma devices with square trench cathode cavities having cross sections of (10 mum)(2) or (30 mum)(2) and a depth of 200 mum have been fabricated and operated successfully in the rare gases and Xe/O-2 mixtures at pressures (300 K) up to 1100 Torr. The (10 mum)(2) structures exhibit electrical characteristics that contrast with the behavior of larger devices and may indicate the onset of the breakdown of pd scaling. Also, a distinct minimum in the ignition voltage of 10 mum square devices is observed for pdsimilar or equal to0.9 Torr cm (p and d are the Ne gas pressure and microcavity cross-sectional dimension, respectively). Strong emission on the 2 (1)Sigma(+)-->1 (1)Sigma(+) transition of XeO in the green (similar to510-560 nm) is observed in mixtures of Xe (300-700 Torr) and O-2 (1-10 mTorr). (C) 2004 American Institute of Physics.