Patent · US Active

Lithographic method

US9823572B2 · kind B2 · utility

2Cited by
21References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 17, 2014
Grant dateNov 21, 2017
Priority date
Expiry dateJun 17, 2034

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH05H2007/041
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A method of patterning lithographic substrates that includes using a free electron laser to generate EUV radiation and delivering the EUV radiation to a lithographic apparatus which projects the EUV radiation onto lithographic substrates. The method further includes reducing fluctuations in the power of EUV radiation delivered to the lithographic substrates by using a feedback-based control loop to monitor the free electron laser and adjust operation of the free electron laser accordingly, and applying variable attenuation to EUV radiation that has been output by the free electron laser in order to further control the power of EUV radiation delivered to the lithographic apparatus.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.