Simulation of pulsed dielectric barrier discharge xenon excimer lamp

Abstract

Recently, it has been shown that the efficiency of excimer lamps can be drastically increased in a pulsed regime. A one-dimensional simulation of pulsed excimer lamps has been performed by Carman and Mildren (2003 J. Phys. D: Appl. Phys. 36 19) (C&M). However, some computational results of the work of C&M are questionable and need to be revisited. In this paper, a dielectric barrier discharge (DBD) in xenon has been simulated for operating conditions similar to those of C&M to better understand plasma dynamics in a pulsed regime. Our simulation results differ considerably from the computational results of C&M. Although these differences do not affect profoundly the plasma macro parameters measured in the C&M experiments, they offer a better understanding of plasma dynamics in pulsed DBDs and form a solid foundation for computational optimization of excimer lamps. It was found that the dynamics of breakdown and the current pulse depend significantly on the initial densities of species after a previous pulse, and so it is important to accurately simulate the plasma evolution in both the afterglow and active stages. It seems possible to modify the power deposition in the plasma by varying external discharge parameters such as the amplitude and the rise time of the applied voltage, and to modify the plasma composition by changing the pulse repetition rate and plasma decay in the afterglow stage.

Electrical Approach of Homogenous High Pressure Ne/Xe/HCl Dielectric Barrier Discharge for XeCl (308 nm) Lamp

“…It is instructive to note that under these operating conditions of the DBDs, the breakdown occurs rapidly and high energy is deposited in the plasma medium by electrons. Recent investigations [21,24,37,39,40] showed that the use of short pulse with a fast Table 1 List of reaction processes and their rate coefficients used in the present work (T e is the electron temperature)…”

“…It has been investigated using many different excited species, including rare gas excimers, molecular rare gas-halide excimers, and halogen dimers [1,[11][12][13][14][15][16][17]. In particularly, excimer and exciplex lamps are predestined for the lighting industry with a long lifetime (up to 4,000 h), as the current is limited by the dielectric and the working mixture does not have a contact with metal electrodes which avoids any reaction between the discharge and the electrodes or contamination of the gas with evaporated electrode material [2,[18][19][20][21][22][23][24][25]. However, the kinetic processes in the plasma responsible for the enhanced lamp performance and increased efficiency are not well understood and the principal disadvantage of excimer DBD discharge is especially their low efficiency.…”

“…However, the kinetic processes in the plasma responsible for the enhanced lamp performance and increased efficiency are not well understood and the principal disadvantage of excimer DBD discharge is especially their low efficiency. Furthermore in order to optimize the discharge luminance efficiency, several experimental, theoretical and detailed computer-modeling studies of the plasma kinetics in pulse-excited DBDs have been realized in the last decade [17][18][19][20][21][22][26][27][28][29][30][31][32][33][34][35][36][37][38]. It has been shown that the efficiency of excimer lamp can be increased up to 60% by employing a fast rise-time and a short pulsed voltage excitation [21,24,37,39].…”

One-dimensional modelling of DBDs in Ne–Xe mixtures for excimer lamps

“…In this work, a secondary emission coefficient [24,47,60,61,74] of 0.25 has been assumed for neon ions. Usually, in DBD's configuration for display panels or lamps a MgO thin film is deposited above the dielectric layers in order to protect the dielectric layers, and decrease the breakdown voltage due to the relatively large value of the secondary electron emission coefficient of MgO bombardment by neon ions.…”

“…The model used by Carman et al [22,49,50] analyzes the spatiotemporal evolution of species populations and electrical parameters. Also, in order to investigate the spatiotemporal characteristics of the short-pulsed DBDs in pure xenon, a 1D and 2D fluid models was used by Bogdanov et al [24,51]. S. Belezenai et al in Ref.…”