Absolute UV and VUV emission in the 100-400 nm region from 13.56 MHz driven hollow slot microplasmas operating in open air

Summary form only given. We present absolute optical emission spectra in the 110-400 nm region from radio-frequency driven (13.56 MHz) hollow slot microplasmas operating in open air at atmospheric pressure. Spectra are presented for gas flows through the micro-electrodes of argon and helium with small admixtures of hydrogen and nitrogen into open air. The spectra are discussed in terms of species origin and magnitude of the dominant emission lines. Atomic O and N lines dominate the 110-200 nm region whereas in the 200-400 nm region, NO, N/sub 2/, N/sub 2//sup +/ and NH molecular lines are strongest. The role of the N/sub 2/ (A 3/spl square/u+) state in the open air micro-plasmas is discussed and the 2nd positive system of molecular nitrogen, (N/sub 2/ (C 3/spl square/g-B 3/spl square/g)), is used to measure the rotational (gas) temperature. Finally, we compare the efficiency and magnitude of light emission from the open air microplasmas with values attainable from commercial sealed mercury lamps in the UVB and UVC regions.