Power couplers for the ILC

Fundamental power couplers are critically important components in all superconducting accelerators. Power couplers provide the vacuum and thermal interface between the superconducting cavity and the room temperature waveguide components and transmit microwaves generated by the high power microwave source. Power couplers must be extraordinarily clean and reliable to ensure that they meet the stringent requirements associated with superconducting accelerators. CPI power couplers are manufactured to our customer's specifications using processes which are standard to the vacuum electron device industry as well as processes which are specific to power couplers. To meet our customer's requirements, we have developed the capability of plating high residual resistivity ratio (RRR) copper on stainless steel. Plating is done in-house under carefully controlled conditions. Our high-RRR-copper plating has been qualified by CNRS-Orsay and Cornell. We have developed the capability of applying TiN coatings to ceramic windows. TiN coating is done in- house under carefully controlled conditions. Our TiN coating process has been qualified at DESY. Using these processes, CPI has manufactured over 50 power couplers of various designs. This year we will manufacture an additional 50 power couplers. This paper will focus on power couplers for the International Linear Collider (ILC). In particular, we will discuss some of the challenges to be faced during the manufacture of tens of thousands of power couplers for the ILC. These challenges were identified during our recent cost study for the ILC RF unit.