Patent ID: 9110390
Filing Date: 2015-08-18
Classification: B82Y,C23C,G02B,G03F,G21K

Abstract:
1. A method of in situ treating an optical component reflecting at least one of EUV and soft X-ray radiation in an optical device, the at least one of EUV and soft X-ray radiation being provided from a radiation source, said radiation source being operable to generate the at least one of EUV and soft X-ray radiation during a normal operation of said radiation source, said radiation source not generating the at least one of EUV and soft X-ray radiation during operational pauses of said radiation source, said optical component being arranged in a vacuum chamber of said optical device and comprising at least one reflecting surface having a top layer of at least one surface material, the method comprising the acts of: providing at least one source for providing said at least one surface material in said chamber; and depositing said at least one surface material from said at least one source on said at least one reflecting surface during at least one of the normal operation and the operational pauses of said optical device in order to at least one of cover, substitute deposited contaminant material and compensate for ablated surface material, wherein said at least one surface material is deposited by sputter deposition; and moving said at least one source close to said at least one reflecting surface during the operational pauses of said radiation source and moving said at least one source away from said at least one reflecting surface during the normal operation of the radiation source.