Nanometric polishing of lutetium oxide by plasma-assisted etching

Abstract

Plasma-assisted etching, in which the irradiation of hydrogen plasma and inorganic acid etching are integrated, is proposed as a novel polishing method for sesquioxide crystals. By means of this approach, low damage and even damage-free surfaces with a high material removal rate can be achieved in lutetium oxide surface finishing. Analysis of transmission electron microscopy and X-ray photoelectron spectroscopy reveal that plasma hydrogenation converts the sesquioxide into hydroxide, which leads a high efficient way to polish the surfaces. The influences of process conditions on the etching boundary and surface roughness are also qualitatively investigated using scanning electron microscope and white light interferometry. The newly developed process is verified by a systematic experiment.

Keywords

Plasma-assisted etching / Lutetium oxide / Surface roughness / Subsurface damage

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Funding

National Key Research & Development Program(No. 2016YFB1102203)

National Natural Science Foundation of China http://dx.doi.org/10.13039/501100001809(No. 61635008)

State Administration of Foreign Experts Affairs http://dx.doi.org/10.13039/501100003512(No. B07014)

National Science Fund for Distinguished Young Scholars(No. 51605327)