High Performance Material Technologies for Advanced Circuit Assemblies and MCMs

Hybrid 3d integrated circuits at millimeter-wave frequencies — advantages and trends

“…At mm-wave frequencies, photo-printed dielectric materials (HERAEUS ink KQ 110 [5] ) are employed to ensure punctual interconnections between the different layers by means of miniature via holes (diameter: 40-50 µm). Notes that laser drilling can also be considered to achieve smaller diameters (#10 µm).…”

Theoretical and experimental study of various types of compensated dielectric bridges for millimeter-wave coplanar applications

“…The metallic layer is then directly screen-printed, or screen-printed and etched, on the upper side of the dielectric layers. In our case, the dielectric material used is a photosensitive Heraeus ink (KQ 110) with a low-permittivity value equal to 3.9 and dielectric losses of 5×1 0 −5 [2]. With this ink, low-loss propagation characteristics have been observed over a 1-50-GHz frequency band, with "on wafer" measurements, carried out on simple transmission lines.…”

“…Obviously, the characteristic impedance and effective permittivity of the basic coplanar waveguide are significantly modified in the bridge region. Taking into account the low dispersive characteristic of the coplanar technology, these variations can be calculated in a first approximation with a static finite-difference method [2]. In this study, bridges were modeled by an equivalent transmission line, taking into account the modified electrical parameters of this local multilayer structure.…”