UV radiation sources operating in an abnormal microdischarge regime

Recently we proposed a new design approach for microdischarge plasma sources and microdischarge arrays [1]. The major improvement comes from the fact that the ceramic dielectric layer is sintered directly on the metal cathode. The discharge channels are drilled in the dielectric layer mechanically or by laser. This design approach excludes the undesirable cathode spot spread, which usually occurs if dielectric is mechanically pressed on the cathode surface. Another advantage is a possibility of efficient cooling. The electrical characteristics of a single microdischarge and microdischarge array operating in abnormal regime were investigated in different gas mixtures (He, Ar, Xe, He-Ar-Xe, He-Xe-HCl) at different gas pressures and configurations of the discharge set-up. The studied set-up allows to achieve discharge voltages up to 2kV in continuous wave DC mode at gas pressures of 100-200 mbar in He or He-Xe gas mixtures. The obtained results indicate that this kind of discharge can be considered as a low-energy electron-beam source. It can be used for efficient pumping of gas lasers (for instance atomic Xe) or for large area planar VUV light sources based on excimers with relatively high excitation threshold (for instance He_2 or Ne_2 dimers). 1. RU.Patent N^o 2172573