Prediction of Fluctuations in Plasma-Wall Interactions Using an Equipment Engineering System

The fluctuations in etch rates caused by changes in chamber conditions were studied. Excess deposition of C-F polymer on the chamber wall increased CFx density while H was consumed by the polymer and/or was deactivated on the conductive surface of Si electrodes. The change in radical densities had a clear relationship with the SiN etch rate. The etch rate was accurately predicted by statistical analysis using equipment engineering system (EES) data and optical emission spectroscopy (OES) signals which were extracted by considering both the physical model and the results of statistical analysis. (C) 2009 The Japan Society of Applied Physics