Abstract: Real time monitoring of a plasma etching process is performed by monitoring the intensity of a specific wavelength created by the plasma. Changes in the intensity of the plasma wavelength indicate the end-point in time for the process. The end-point value is compared with one or more reference values to determine whether the etching process is stable. End-point values outside of a pre-selected range of values is indicative of unstable processing conditions, thus allowing termination of the etching process before unstable conditions can result in substantial scrap.