公开(公告)号：WO2019170503A1

公开(公告)日：2019-09-12

申请号：PCT/EP2019/054924

申请日：2019-02-28

Applicant: ASML NETHERLANDS B.V.

Inventor： MA, Yue ,  KEMPEN, Antonius, Theodorus, Wilhelmus ,  HUMMLER, Klaus, Martin ,  MOORS, Johannes, Hubertus, Josephina ,  ROMMERS, Jeroen, Hubert ,  VAN DE WIEL, Hubertus, Johannes ,  LAFORGE, Andrew, David ,  BRIZUELA, Fernando ,  WIEGGERS, Rob, Carlo ,  GOMES, Umesh, Prasad ,  NEDANOVSKA, Elena ,  KORKMAZ, Celal ,  KIM, Alexander, Downn ,  DUARTE RODRIGUES NUNES, Rui, Miguel ,  VAN DIJCK, Hendrikus, Alphonsus, Ludovicus ,  VAN DRENT, William, Peter ,  JONKERS, Peter, Gerardus ,  ZHU, Qiushi ,  YAGHOOBI, Parham ,  WESTERLAKEN, Jan, Steven, Christiaan ,  LEENDERS, Martinus, Hendrikus, Antonius ,  ERSHOV, Alexander, Igorevich ,  FOMENKOV, Igor, Vladimirovich ,  LIU, Fei ,  JACOBS, Johannes, Henricus, Wilhelmus ,  KUZNETSOV, Alexey, Sergeevich

IPC: G03F7/20 ,  G02B5/08 ,  G21K1/06 ,  H05G2/00 ,  G02B1/14

Abstract: Degradation of the reflectivity of one or more reflective optical elements in a system (SO) for generating EUV radiation is reduced by the controlled introduction of a gas into a vacuum chamber (26) containing the optical element. The gas may be added to the flow of another gas such as hydrogen or alternated with the introduction of hydrogen radicals.