Antenna-in-Package and Heterogeneous Integration for Sub-THz Wireless Systems

Future wireless communication, sensing, and high-capacity connectivity systems are increasingly moving toward frequencies beyond 100 GHz. The large bandwidth available at sub-terahertz frequencies can enable extremely high data rates and high-resolution sensing. However, at these frequencies, the package can no longer be considered merely as an electrical and mechanical interface between integrated circuits and the outside world. Transmission lines, vertical transitions, dielectric materials, manufacturing tolerances, antennas, and semiconductor devices together determine the RF performance of the complete system.

Conventional PCB and packaging technologies face increasing conductor, dielectric, radiation, and transition losses at sub-THz frequencies. At the same time, semiconductor-based RF interposers can provide excellent electrical performance but may come with increased fabrication complexity and cost. Therefore, advanced organic IC-substrate technologies offer an interesting alternative, provided that their materials, layer stacks, interconnect structures, and manufacturing processes can be optimized for operation beyond 100 GHz.

In this PhD, the PhD student will investigate advanced organic packaging technologies for antenna-in-package and heterogeneous RF integration at sub-THz frequencies, with an initial focus on the D-band (110–170 GHz). The objective will be to establish the electromagnetic design principles and technology requirements that enable low-loss interconnects, high-performance antennas, and heterogeneous integration of RF integrated circuits within scalable organic packages. A central research question will be how the package technology and RF architecture should be co-designed rather than optimized independently. Organic package implementations will therefore be benchmarked against alternative heterogeneous integration technologies, including RF-optimized silicon interposers. This comparison will identify where organic technologies provide competitive performance and where changes in materials, layer thicknesses, manufacturing tolerances, or stack-up architecture are required.

Building on these results, the PhD will investigate antenna-in-package architectures in which radiating elements, feed networks, transitions, and RF interfaces are integrated directly into the package. Different antenna concepts will be explored with emphasis on bandwidth, radiation efficiency, polarization, array scalability, thermal and mechanical constraints, and compatibility with package manufacturing. The interaction between antennas and nearby package structures, interconnects, integrated circuits, and other components will form an important part of the research.

The work will subsequently progress toward heterogeneous integration of sub-THz integrated circuits and antennas. Package-to-chip transitions, RF interconnects, integrated passive structures, antennas, and potentially III-V RF components will be investigated as elements of a complete RF module. Electromagnetic co-design techniques will be developed to minimize losses and parasitic effects across the IC–package–antenna signal path. A key aspect of the PhD will be the transition from electromagnetic simulation to experimentally validated hardware. The PhD student will design dedicated test vehicles that progressively increase in complexity. Designs will be fabricated using advanced packaging technologies and characterized using sub-THz measurement facilities. S-parameter measurements, antenna gain and radiation patterns, and detailed comparison between simulation and measurement will be used to establish experimentally validated design guidelines. The final objective is to demonstrate how advanced organic packaging can evolve from a conventional IC substrate into a functional RF platform for next-generation communication and sensing systems. The resulting design methodologies and technology guidelines will provide insight into the trade-offs between RF performance, manufacturing complexity, scalability, and cost, while contributing toward scalable antenna-package-IC integration for future 6G and sub-THz systems.

The PhD student will become part of both imec, Leuven and Ghent University, sharing their time between both institutions. At imec, PhD student will interact with experts in advanced RF design, heterogeneous integration, semiconductor technology, packaging, and sub-THz characterization. At Ghent University, PhD student will join the IDLab Electromagnetics research group and collaborate with researchers working on antennas, propagation, electromagnetic modeling, and future wireless systems.

The research will combine electromagnetic theory, antenna and microwave engineering, advanced packaging, numerical simulation, fabrication, and experimental characterization, providing a unique opportunity to investigate sub-THz systems from fundamental electromagnetic structures through to integrated hardware demonstrators.