High selectivity nitride to oxide etch process

摘要

The process parameters according to which the AMT 8310 RIE plasma etcher operates are altered so as to increase the nitride to oxide selectivity of the AMT 8310 RIE plasma etcher from approximately 3:1 to approximately 5:1, thereby allowing for the fabrication of modern semiconductor devices having oxide films significantly less thick than 325 ANGSTROM . In this manner, the present invention eliminates the need for an expensive upgrade in etching equipment to realize an increase in nitride to oxide selectivity. The semiconductor device is electrically biased at 100-300 volts, and freon and oxygen have a flow rate ratio of approximately 1:1.