Efficient UV emission of addressable pixel arrays of Si microplasma devices

Summary form only given. The array of Si microcavity plasma device is a new light source for generating emission with high efficiency and pixel-to-pixel uniformity. As the device operates with specific power loading higher than tens of kW/cm³, it can achieve any region of emission wavelengths between UV and IR through the discharge of various atomic or molecular gases. In this paper, we report the performance of AC-excited Si microplasma arrays having (50 mum)² and (100 mum)² microcavity dimension operated in the atmospheric pressures of molecular UV emitters. Each microcavity is comprised of a pair or three metal electrodes which are individually patterned and embedded in the multilayer structure. The devices operated in the mixtures of molecular gases such as N₂, H₂, D₂, H₂O in Ar. All the arrays exhibit stable, reproducible behavior with AC (sinusoidal) or bipolar waveform excitation at total gas pressures of 400-800 torr. In case of Ar/D₂ discharge, operating voltages as low as 200 V of RMS voltage are observed in Ar/D₂ gas pressure of 500 torr and excitation frequency of 20 kHz. The emission spectrum shows strong D₂ continuum band over the wavelength range of 250-400 nm. (100 mum)² microcavity device shows higher UV emission intensity and efficiency than (50 mum)² device in a given condition. The discharge properties in various UV emitting gases will be discussed in detail