Characterization of chemically assisted ion beam etching and Form birefringence structure fabrication in GaAs using SU-8

摘要

We describe an approach to use the thin layer of SU-8 submicron pattern produced by holographic lithography as dry etching mask in chemically assisted ion beam etching (CAIBE) system. The effect of chlorine gas flow on etched sidewall was investigated; by matching the lateral etch and deposition rate, etching selectivity of about 7:1 has been achieved with vertical and smooth sidewall and damage-free upper portion of the etched structure. As an application, a half wavelength retardation plate for 1.55 μm wavelength was designed, fabricated and characterized.