Laser produced plasma (“LPP”) extreme ultraviolet light (“EUV”), e.g., at wavelengths below about 50 nm, using plasma source material targets in the form of a jet or droplet forming jet or droplets on demand comprising plasma formation material, e.g., lithium, tin, xenon, in pure form or alloy form (e.g., an alloy that is a liquid at desired temperatures) or mixed or dispersed with another material, e.g., a liquid. Delivering this target material to a desired plasma initiation site, e.g., at a focus of a collection optical element presents certain timing and control problems that applicants propose to address according to aspects of embodiments of the present invention.
U.S. Pat. No. 6,541,786, entitled PLASMA PINCH HIGH ENERGY WITH DEBRIS COLLECTOR, issued on Apr. 1, 2003, to Partlo, et al, and co-owned by applicants' assignee, and patents issued on parent applications of the application from which the U.S. Pat. No. 6,541,786 patent issued, and U.S. Pat. No. 4,589,123, entitled SYSTEM FOR GENERATING SOFT X RAYS, issued to Pearlman et al. on May 13, 1986, and Japanese laid open applications 08-321395, published on Dec. 3, 1996, with Kamitaka et al. inventors and assigned to Nikon Corp, and 09-245992, published on Sep. 19, 1997, with inventors Kamitaka et al. and assigned to Nikon Corp., relate to debris management in the vicinity of the exit opening for plasma generated EUV light sources.