Ultrasmooth Polishing with Sub-Angstrom Roughness on Fused Silica Surface

Abstract

In order to superpolish fused silica surface, a non-contact polishing method is applied, which is called as computer numerical-controlled (CNC) micro-jet polishing (MJP) technology developed on the base of the hydrodynamic mechanism. In this paper, both the theory and the techniques about this new polishing technology are introduced in detail, and the curved surface of fused silica was polished. The results demonstrate that no new scratches were produced when the nanoparticles removed the atoms away from the surface. The roughness decreased monotonously with the removal of subsurface damage layer. And ideal Ultrasmooth surface without scratches was achieved by MJP with waveness less than 0.2nmrmsRMS while the high-spatial frequency roughness less than 0.1nmrmsRMS (sub-angstrom).