Patent ID: 8411815

Claim:
A source-collector system for extreme ultraviolet (EUV) or X-ray radiation, comprising in order along a system axis: a mirror; a grazing incidence collector having an intermediate focus and input and output ends; a laser-produced plasma (LPP) source adjacent the output end of the grazing incidence collector; wherein the LPP source includes a fuel target irradiated by a laser beam to generate the EUV or X-ray radiation, wherein the laser beam is reflected from the mirror and directed to pass in a direction through the grazing incidence collector from the input end to the output end and along the system axis to the fuel target, and wherein the fuel target emits the EUV or X-ray radiation in response to being irradiated by the laser beam, the EUV or X-ray radiation having a peak emission in the direction opposite to the direction of the laser beam; and wherein the grazing incidence collector collects a portion of the EUV or X-ray radiation and directs it to the intermediate focus, which resides on the system axis beyond the mirror.