Fabrication tolerances in low cost antenna substrates at 60 GHZ

For wireless IoT nodes in future 5G networks, on-package antenna arrays improve performance and lower costs, but to accomplish industry standards, this approach demands for low-cost package materials which have appropriate mechanical as well as electromagnetic properties. From this point of view, specific mold materials are quite promising. But a reliable and reproducible fabrication of mold substrate is hard to facilitate. Dealing with mold thickness variations, warpage, and shrinkage becomes a serious challenge in the design of mm-wave structures and antennas, see pictures below. On the implementation of a 4x4 phased-array for 60 GHz applications, this presentation will give an approach for modeling these material deformations, concerning model parameterization, simulation time and memory usage. Particular deformations as well as combinations of various deformation scenarios are regarded. The impact of material deformation on radiation characteristics and bandwidth will be investigated in order to provide fabrication constraints and thus reducing the subset of suitable materials.