Measurements of structures for vacuum electronic sources manufactured by 3D printing

Periodic structures that reduce the velocity of electromagnetic wave propagation are widely used in electron beam driven microwave vacuum electronic sources. When the frequency increases into the mm-wave region such structures become difficult to manufacture because of the small physical dimensions. “Additive Manufacturing” or “3D printing” offers the possibility of constructing certain types of components quickly, efficiently and relatively inexpensively. Many questions arise however, including what structural resolution is obtainable, the surface roughness, surface electrical resistivity and vacuum compatibility. To address some of these questions the performance of a periodic structure manufactured using a 3D printing technique and designed for W-band operation (75-110GHz) is evaluated and reported in the present work.