Multilayer waveguide structures for radiofrequency antennas, radiofrequency antennas comprising the same

Abstract

A multilayer waveguide structure () for a radiofrequency antenna comprises: —a stack of substrates () separated by each other by interface layers (), the substrates having a permittivity larger or equal to 1, and —metal vias () or metal trenches formed in at least some of the substrates. Each interface layer () comprises a first metal layer (), a second metal layer (), and an adhesive layer () between the first metal layer () and the second metal layer (). At least one of said interface layer () comprises patterned structures (R), for which the adhesive layer () is thinner while still preventing a direct electric contact between the first and second metal layers (), and each said patterned structure (R) is located near or at the base or the top of a metal via () or metal trench.