An optical RIE process uniformity control sensor

Summary form only given. Radial etch process measurement techniques have been compared using a GEC reference cell for argon sputter etching of silicon oxide. Post process reflectometry measurements, Langmuir probe studies and optical tomography results were used to study the process uniformity at various set points. The purpose of this experiment is to demonstrate the ability of a small window plasma tomography sensor to function as a process diagnostic, allowing in situ process monitoring and an alternative uniformity measurement to post process wafer measurements. An overview of the sensor geometry, signal reconstruction, and comparison to Langmuir probe and reflectometry measurements is presented.