公开(公告)号：US09606446B2

公开(公告)日：2017-03-28

申请号：US14732248

申请日：2015-06-05

申请人： Carl Zeiss SMT GmbH

发明人： Norbert Wabra ,  Boris Bittner ,  Martin Von Hodenberg ,  Hartmut Enkisch ,  Stephan Muellender ,  Olaf Conradi

IPC分类号： G03F1/22 ,  G03F1/24 ,  G03F7/20 ,  G02B5/08 ,  G21K1/06 ,  G02B17/06 ,  G02B27/10 ,  B82Y10/00

CPC分类号： G03F7/702 ,  B82Y10/00 ,  G02B5/0816 ,  G02B5/0891 ,  G02B17/0663 ,  G02B27/1033 ,  G03F7/70308 ,  G03F7/70316 ,  G03F7/70916 ,  G03F7/70958 ,  G21K1/062

摘要： A reflective optical element of an optical system for EUV lithography and an associated manufacturing method. The reflective optical element (20) includes a multilayer system (23, 83) for reflecting an incident electromagnetic wave having an operating wavelength in the EUV range, the reflected wave having a phase φ, and a capping layer (25, 85) made from a capping layer material. The method includes determining a dependency according to which the phase of the reflected wave varies with the thickness d of the capping layer, determining a linearity-region in the dependency in which the phase of the reflected wave varies substantially linearly with the thickness of the capping layer, and creating a thickness profile in the capping layer such that both the maximum thickness and the minimum thickness in the thickness profile are in the linearity-region.