Copper Reconsidered: Material Innovations to Transform Vacuum Electronics

Copper is critical to the manufacturing of vacuum electronic devices due to its high electrical and thermal conductivities. It enables high RF performance while maintaining low thermal losses. Copper is also responsible for some of the challenges: RF power output is often limited by the strength of copper and RF breakdown is induced by copper transformation at the vacuum surface. Recent advances in understanding of RF interaction with copper offer insight into its limitations and how they may be mitigated. Emerging manufacturing technologies, such as electron beam melting of copper, can be employed to achieve a stronger copper state in the RF structures, opening opportunities for higher power and more compact vacuum electronics. As copper focused additive manufacturing evolves, strengthening mechanisms can be incorporated into the material to produce desired material properties locally, further enhancing performance capabilities of vacuum devices.