Patent ID: 9713240
Date: 2017-07-18
CPC Classifications: H05G

Claim:
1. A method comprising: providing a target material that comprises a component that emits extreme ultraviolet (EUV) light when converted to plasma; directing a first beam of radiation toward the target material to deliver energy to the target material to modify a geometric distribution of the target material to form a modified target; directing a second beam of radiation toward the modified target, the second beam of radiation converting at least part of the modified target to plasma that emits EUV light; controlling a radiant exposure delivered to the target material from the first beam of radiation to within a predetermined range of radiant exposures by estimating an expansion rate of the modified target; and stabilizing a power of the EUV light emitted from the plasma by controlling the radiant exposure delivered to the target material from the first beam of radiation to within the predetermined range of radiant exposures.