MONITORING OF FILM CHARACTERISTICS DURING PLASMA-BASED SEMICONDUCTOR PROCESSING USING OPTICAL EMISSION SPECTROSCOPY

摘要

A method and system to monitor characteristics of films by sensing the spectral emissions of a plasma to which the films are exposed. As a result, the method includes sensing optical energy produced by the plasma. The optical energy has a plurality of spectral bands associated therewith, a subset of which is identified as including information corresponding to the film characteristics. The film characteristics are then measured as a function of this information. To increase the accuracy of the measurements, in one embodiment of the present invention a subgroup of the plurality of spectral bands is observed that has data associated that is substantially independent of the characteristics of interest. The characteristics are then measured as a function of both the information and the data.