Etching of 6H‐SiC and 4H‐SiC using NF 3 in a Reactive Ion Etching System

Abstract

The use of pure source gas in reactive ion etching of bulk and epitaxy. Si‐face, 6H‐SIC, and 4H‐SIC is reported. The effects of RF power and chamber pressure on etch rate and surface morphology are discussed. A process developed for a smooth, residue‐free etch, with a relatively high etch rate of ∼1500 Å/min is examined using scanning electron microscopy and Auger electron spectroscopy surface analysis. The process developed had a self‐induced dc bias ranging from 25 to 50 V, a forward RF power of 275 W (1.7 W/cm2), chamber pressure of 225 mT, and a flow rate between 95 and 110 sccm. No chemical residue or aluminum micromasking was observed on any of the samples etched with the above process.