Microhollow cathode discharge excimer light sources

Conference · Thu Jul 01 04:00:00 EDT 1999

OSTI ID:20067655

El-Habachi, A; Moselhy, M; El-Dakroury, A; Schoenbach, K H

Microhollow Cathode discharges are non-equilibrium, high pressure, direct current discharges. By reducing the diameter of the cathode opening in a hollow cathode discharge geometry to values in the sub millimeter range the authors were able to operate discharges in argon and xenon in a direct current mode up to atmospheric pressure. They have shown that these discharges are intense source of xenon and argon excimer radiation peaking at wavelengths of 172 nm and 130 nm, respectively. Spatially resolved measurements of the excimer source in xenon have been performed. The source was found to be cylindrical along the axis of the electrodes. Its radius increases with current and decreases with pressure. Stacking the discharges, operating them in series, holds the promise for the generation of a laser medium with sufficient length to provide the required threshold gain for a dc excimer laser. Experimental studies of the gain of the plasma column in microhollow cathode discharges are underway. Excimer efficiencies, defined as the ratio of optical to electrical power, of 6% to 9% have been achieved. Further increase of the efficiency seems to be possible; according to the modeling results, efficiencies of 30% to 40% may be obtainable. The effect of various parameters such as electrode geometry, gas flow and pulsed versus cw operation on the excimer efficiency is being studied with the goal to optimize the discharge.

• Research Organization: Old Dominion Univ. Norfolk, VA (US)
• OSTI ID: 20067655
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
ARGON
EFFICIENCY
ELECTRIC DISCHARGES
EXCIMER LASERS
HOLLOW CATHODES
OPTIMIZATION
XENON