Novel Coating for Suppression of Multipactor in High Power Microwave Devices

Multipactor is an incessant problem that plagues numerous commercial and military systems, including satellites and particle accelerator components such as klystrons and free electron lasers (FELs). Metallic surfaces within High Power Microwave (HPM) devices are susceptible multipactor due to the high Secondary Electron Emission Coefficient (SEEC) of internal surfaces. Current solutions, including traditional coatings such as Titanium Nitride (TiN) or use of magnetic systems to suppress SEE, are insufficient to support HPM operations at high frequencies (1 – 40GHz) and high operating powers. Nokomis has developed a unique thin film material with an extremely low SEE that does not affect the performance of Radio Frequency (RF) devices. The material was successfully demonstrated through Phase I as suitable for HPM applications through testing and simulation. Under this Phase II effort, HPM devices will be coated and tested in representative environments to demonstrate the benefits and advantages of the developed technology. Nokomis will further enhance the developed DLC coating, improve the deposition methodology to accommodate closed and complex HPM device geometries, and perform in line high power high frequency testing to demonstrate performance gains. The achievement of Phase II technical objectives will position this technology for rapid commercialization, enabling the enefits of multipactor mitigation and/or suppression to be leveraged by the HPM community. The success of this effort will address performance limiting problems currently experienced in equipment used for multiple fields, including communications, manufacturing, radar, medical diagnostics and radiotherapy. Key Words: multipactor, multipactor mitigation, thin film, coating, carbon nanocoating, high power microwave, high power high frequency devices