Modeling Filamentary Transitions in an ArF Excimer Laser

Filament formation in excimer laser discharge chambers often leads to premature termination of optical pulses, serving as a key factor affecting laser spatial homogeneity and energy stability. This study develops a 0-2D hybrid discharge model for ArF laser discharge chambers to simulate non-uniform glow-filament discharge transitions. The localized halogen depletion near hotspots during filament growth are observed, with discharge non-uniformity evolution qualitatively consistent with experimental observations. We make semi-quantitative analysis about the impact of filaments on glow discharge energy and total ArF* production, finding that the ArF* yield per unit energy in filament regions was found to be only 10\%-12\% of that in glow regions. By adjusting magnetic pulse compression (MPC) excitation circuit parameters, the energy allocation between filaments and glow discharge are improved, reducing laser energy drop caused by filaments.