Reactive Ion Etching of PECVD Silicon Dioxide (SiO2) Layer for MEMS application

摘要

A reactive ion etching (RIE) process has been developed to etch up to 1-micrometer (1 m) layer of low stress SiO2 (Silicon Dioxide) Plasma Enhanced Chemical Vapor Deposition (PECVD) film compatible for MEMS research applications. Etch rates from as low as 123 nm/min at 100 W to as high as 721 nm/min at 900 W powers were demonstrated using fluorocarbon (CF4) reactive gas plasma. RIE selectivity (SiO2/PR-Photoresist) was 3:1 at 900W. The measured thickness variation was 0.13 m on 4-inch substrate for 1 m thick SiO2 film.