METHOD OF ETCHING SILICON DIOXIDE

摘要

Silicon dioxide is etched at about five times the rate of silicon in a moderate vacuum gas plasma formed from a mixture of CF4 and oxygen wherein the mixture contains above about 5 to about 15 percent by volume CF4 so that films of silicon dioxide on silicon can be etched to the silicon surface without excessive attack on the silicon. Silicon dioxide is etched at about three times the rate of silicon nitride so that silicon nitride can be used as an etch mask for the process.