Method and apparatus for generating radiation

摘要

A radiation source (e.g., LPP—laser produced plasma source) for generation of extreme UV (EUV) radiation has at least two fuel particle streams having different trajectories. Each stream is directed to cross the path of an excitation (laser) beam focused at a plasma formation region, but the trajectories are spaced apart at the plasma formation region, and the streams phased, so that only one stream has a fuel particle in the plasma formation region at any time, and so that when a fuel particle from one stream is generating plasma and EUV radiation at the plasma generation region, other fuel particles are sufficiently spaced so as to be substantially unaffected by the plasma. The arrangement permits potential doubling of the radiation intensity achievable for a particular fuel particle size.

主权项

1. A method of generating radiation for a lithography apparatus, the method comprising:
directing a first stream of fuel particles along a first trajectory to cross a path of an excitation beam within a plasma formation region; directing a second stream of fuel particles along a second trajectory to cross the path of the excitation beam within the plasma formation region; and wherein the fuel particles are excited by the excitation beam to form a plasma to generate radiation within the plasma formation region, wherein the first and second trajectories are spaced apart within the plasma formation region and the fuel particles of the first and second streams are timed to cross the excitation beam, such that when a fuel particle from one stream is crossing the path of the excitation beam and generating a plasma, an adjacent particle from the other stream is spaced sufficiently far from the generated plasma to be substantially unaffected by the generated plasma.