US 12,452,987 B2
High-power compact VUV laser-sustained plasma light source
Ilya Bezel, Mountain View, CA (US)
Assigned to KLA Corporation, Milpitas, CA (US)
Filed by KLA Corporation, Milpitas, CA (US)
Filed on Feb. 9, 2024, as Appl. No. 18/438,025.
Claims priority of provisional application 63/446,911, filed on Feb. 20, 2023.
Claims priority of provisional application 63/445,307, filed on Feb. 14, 2023.
Prior Publication US 2024/0274430 A1, Aug. 15, 2024
Int. Cl. H05G 2/00 (2006.01); H01J 61/02 (2006.01); H01J 61/16 (2006.01); H01J 61/26 (2006.01); H01J 61/40 (2006.01); H01J 65/04 (2006.01)
CPC H05G 2/008 (2013.01) [H01J 61/025 (2013.01); H01J 61/16 (2013.01); H01J 61/26 (2013.01); H01J 61/40 (2013.01); H01J 65/04 (2013.01)] 35 Claims
OG exemplary drawing
 
1. A laser-sustained plasma broadband light source comprising:
a gas containment structure containing a mixture of a first noble gas and a second noble gas;
a filter tube positioned within the gas containment structure;
an input optical window;
a laser pump source configured to generate an optical pump, wherein the laser pump source is configured to direct the optical pump through the input optical window to sustain a plasma within the filter tube, wherein the plasma generates broadband light;
wherein the first noble gas absorbs a portion of the broadband light within a first wavelength band and a second wavelength band;
wherein the filter tube is configured to absorb a portion of the broadband light having a wavelength below a selected wavelength threshold, wherein absorption of broadband light by the first noble gas and the filter tube provide long-pass filtering of broadband light below the selected wavelength threshold to protect one or more downstream optical elements from damage;
an output optical window configured to transmit filtered broadband light out of the gas containment structure;
a gas inlet; and
a gas outlet, wherein the gas inlet and gas outlet are configured to generate a reverse vortex flow pattern within the filter tube.