title: Chemical mechanical polishing to improve the efficiency uniformity of beam sampling grating.
abstract: In order to improve the efficiency uniformity of large-aperture beam sampling gratings (BSGs), a conventional chemical mechanical polishing (CMP) process of fused silica by CeO₂ slurry is proposed to modify their groove profiles. With the proposed CMP process, the efficiency uniformity of several BSGs with an aperture of 430  mm×430  mm has been successfully controlled within an rms of 5%. The proposed CMP process is an effective method to improve the efficiency uniformity of large-aperture BSGs. Using the proposed CMP process, the requirement of the uniformity of the holographic ion beam etching process can be released in the realization of large-aperture BSGs.
authors.forename: Huanle
authors.initials: H
authors.lastname: Rao
authors.forename: Ying
authors.initials: Y
authors.lastname: Liu
authors.forename: Zhengkun
authors.initials: Z
authors.lastname: Liu
authors.forename: Keqiang
authors.initials: K
authors.lastname: Qiu
authors.forename: Xiangdong
authors.initials: X
authors.lastname: Xu
authors.forename: Yilin
authors.initials: Y
authors.lastname: Hong
authors.forename: Shaojun
authors.initials: S
authors.lastname: Fu