Packed-bed filter for metal fluoride dust trapping in laser discharge chambers

A metal fluoride trap configured to trap metal fluoride dust generated in a gas discharge medium of a gas discharge stage, the metal fluoride trap comprising:

• an electrostatic precipitator;
• and
• a packed-bed filter disposed around the electrostatic precipitator,
• wherein the packed-bed filter comprises a plurality of beads configured to absorb metal fluoride dust in the gas discharge medium.

A method of trapping metal fluoride dust generated in a gas discharge medium of a gas discharge stage in a metal fluoride trap, the method comprising:

• assembling a precipitation tube assembly comprising a plurality of precipitation tubes between a first tube end support and a second tube end support;
• assembling a plurality of packed-bed filters in the precipitation tube assembly around an electrostatic precipitator to form a packed-bed filter assembly, wherein each packed-bed filter comprises a plurality of beads configured to absorb metal fluoride dust in the gas discharge medium;
• inserting the packed-bed filter assembly into the metal fluoride trap;
• directing the gas discharge medium to flow through the metal fluoride trap;
• and
• trapping metal fluoride dust in the packed-bed filter assembly.