Plasma Analyzing And Controlling System With Real-Time Signal Processing
R. W. Paulson, A. Porter, T. Schapp, J. Barney, J. R. Hodor · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1982
Although plasmas are very powerful tools for etching and other operations related to microelectronics, they can vary drastically and are not always predictable. It is in such a dynamically varying and sometimes adverse environment that some of the most critical and delicate circuits are processed. Sensing events in the plasma, real time processing, and plasma control are critical, A real time, low-light-level, continuously observing optical spectrometer is used to indicate the absence or presence of emission or obsorption spectra. Electronically sensing this spectra and fast electronic processing provides the needed sig nals to control the plasma. The system works on light levels below 10-12 watt and obtains processed spectral data in less than 70 microseconds.