Single-step Inductively Coupled Plasma Etching of Sputtered Nb2O5/SiO2 Multilayer Stacks Using Chromium Etch Mask

This paper presents the dry etching characteristics of Nb2O5/SiO2 multilayer stacks deposited using ion beam sputtering. Dry etching is achieved by using a combination of CHF3 and Ar gases in an inductively coupled plasma (ICP)-reactive ion etching system. The effect of the etching parameters such as the gas ratio (CHF3/Ar), radio-frequency power, ICP power, chamber pressure, and temperature is investigated. An etching recipe is optimized to achieve a high etch rate, good selectivity, and optimum etch profile. The optimized etching recipe provides a single step etch solution for both dielectric materials. Furthermore, the deposition and structuring process of a chromium based etch mask is investigated. (C) 2017 American Vacuum Society.