Ultra high-frequency characterization of high-density 3D module

With three-dimensional (3D) packaging technology it is possible to achieve a much smaller package size and weight and a higher integration rate than with planar technology. Increased frequency and shorter distances force us to take into account parasitic effects and interconnections when we design a high-performance device. Parasitic components may cause reflection, distortion, and signal delays. Therefore, accurate models for interconnections, packages, and components are needed for the simulation of applications with high performance. This paper focuses on electrical characterization of vertical interconnections in a stacked 3D structure. The high-frequency response of the vertical interconnections are studied with 3D full-wave software. A high-frequency test module was manufactured and measured. The correlation between simulations and experimental results is analyzed. Finally, we propose an equivalent circuit model for the solder-plated polymer ball used in the vertical interconnection.