Abstract:
The disclosure relates to microwave cavity plasma reactor (MCPR) apparatus and associated tuning and process control methods that enable the microwave plasma assisted chemical vapor deposition (MPACVD) of a component such as diamond. Related methods enable the control of the microwave discharge position, size and shape, and enable efficient matching of the incident microwave power into the reactor prior to and during component deposition. Pre-deposition tuning processes provide a well matched reactor exhibiting a high plasma reactor coupling efficiency over a wide range of operating conditions, thus allowing operational input parameters to be modified during deposition while simultaneously maintaining the reactor in a well-matched state. Additional processes are directed to realtime process control during deposition, in particular based on identified independent process variables which can effectively control desired dependent process variables during deposition while still maintaining a well-matched power coupling reactor state.