Prospects for the Application of Liquid Glass for Smoothing the Surface of Optical Elements

Abstract: It is proposed to use “liquid glasses” of various compositions as substrates for space-based X-ray optical elements. One of the main requirements for such materials is the smallest weight and the possibility of surface treatment. Special requirements are imposed on the surface roughness, which should be less than 1 nm, and the shape accuracy should be at the level of a few nanometers. It is proposed to use a class of compounds based on alkali-metal silicates or strong organic bases as a material that makes it possible to form the required shape and surface roughness, as well as to provide subsequent processing. The effect of smoothing the surface roughness of liquid glass of three different compositions deposited onto chromium and nickel films is studied. The roughness of all surfaces before and after the deposition of structures is measured using an atomic force microscope. The roughness was calculated using the power spectral density function (PSD function). The structures deposited onto the surface were irradiated with accelerated argon ions with an energy of 800 eV. The etching depth and effective roughness were measured. One of the studied compositions shows a satisfactory reduction in the roughness and stability of this effect during ion etching.