Methods of an problems associated with process control of microwave discharges

Summary form only given. The microwave plasma process control problem has been considered. Generic waveguide and cavity microwave plasma reactors have been examined for their controllability, repeatability, and adaptability for automatic control. The controllable, process input variables and output product related variables have been identified for a generic process reactor, and internal reactor variables have been identified for example process applications such as etching and thin film deposition. Control problems associated with discharge stability, process hysteresis, and multiple steady-states, and methods of process feedback have been identified and categorized. These problems/methods have been related to microwave plasma reactor design. Methods of automatic process control have been proposed including techniques for automatic impedance matching electromagnetic field control, and on-line plasma control.