Michigan State University

Fraunhofer Usa, Inc.

Jing Lu

Jes Asmussen

Yajun Gu

Timothy Grotjohn

Michael Frank Becker

Thomas Schuelke

Donnie K Reinhard

David King

Kadek W Hemawan

M Kagan Yaran

Shreya Nad

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.

Methods and apparatus for microwave plasma assisted chemical vapor deposition reactors

New and improved microwave plasma assisted reactors, for example chemical vapor deposition (MPCVD) reactors, are disclosed. The disclosed microwave plasma assisted reactors operate at pressures ranging from about 10 Torr to about 760 Torr. The disclosed microwave plasma assisted reactors include a movable lower sliding short and/or a reduced diameter conductive stage in a coaxial cavity of a plasma chamber. For a particular application, the lower sliding short position and/or the conductive stage diameter can be variably selected such that, relative to conventional reactors, the reactors can be tuned to operate over larger substrate areas, operate at higher pressures, and discharge absorbed power densities with increased diamond synthesis rates (carats per hour) and increased deposition uniformity.

Microwave plasma reactors

Growing community of inventors

East Lansing, MI, United States of America

Jing Lu