Power distribution between electrons and ions in the dielectric barrier discharge in Xe-Cl_2 mixtures and radiation of Xe_2~* and XeCl~* excimer molecules

摘要

Power distribution between electrons and positive and negative ions and effect of the distribution on radiative efficiency of XeCl~* (308 nm) and Xe_2~* (172 nm) excimer molecules in the dielectric barrier discharge in Xe-Cl_2 at various pressures and supply voltages have been studied and discussed. The discharge characteristics were simulated using the 1D fluid model. It was shown that at small chlorine fraction in the mixture ～0.1-1% the most emission of the DBD is observed in the B→X band of XeCl~* molecules at 308 nm: in most cases about 90%-95% of the discharge emission falls on the XeCl~* radiation. Highest emission in the B→X band of XeCl~* is observed when electrons adsorb about 50 or a bit higher percent of the discharge power. In this case an optimum between emission power and radiative efficiency of XeCl~* UV emission is achieved. When the power absorbed by electrons reaches 70%, the radiation efficiency of Xe_2~* (at 172 nm) sharply increases and riches 10-11% at small increase or even decrease in radiation efficiency of XeCl~* (at 308 nm).