Оптимизация технологии изготовления дифракционных Si-решеток треугольного профиля для мягкого рентгеновского и экстремального ультрафиолетового излучения

Abstract

Anisotropic wet etching of vicinal single-crystallyne Si (111)4° wafers was used to obtain blazed gratings with high efficiency for soft X-ray (SXR) and extreme ultraviolet (EUV) applications. An improved experimental technology for the fabrication of triangular Si gratings, both medium frequency (250 and 500 mm-1) and high-frequency 2500 mm-1, is presented. The stages of a Cr mask formation for grooves etching, removing Si protrusions in order to smooth the profile, and polishing the surface to reduce nanoroughness are optimized. This work describes the method for simultaneous (in one process) obtaining a smoothed triangular profile of the Si grating and a polished surface of grooves by wet etching.