Self-expanded microcapillary positive column for highly efficient vacuum ultraviolet sources

We adopted the self-expanded microcapillary positive column from single microhollow cathode discharge as a high efficient vacuum ultraviolet (vuv) sources, employing one power supply circuit with a resistor for easily starting without an additional power supplier and investigated their electrical characteristics and the vuv radiant efficiency, varying the input power. The electrical measurements showed that the discharge passed through two distinct stages: the microhollow cathode discharges stage and the self-expanded microcapillary positive column stage. As a result, the vuv radiant efficiency of the self-expanded microcapillary positive column is about 17 times as high as that of the microhollow cathode discharges at the input power 1.2W.