News: Optoelectronics
9 June 2025
Imec and Ghent University present fully integrated, single-chip microwave photonics system for compact and versatile signal processing
Nanoelectronics research center imec of Leuven, Belgium and two imec research groups at Ghent University (the Photonics Research Group and IDlab) have demonstrated a fully integrated single-chip microwave photonics system, combining optical and microwave signal processing on a single silicon chip (Hong Deng et al, ‘Single-chip silicon photonic engine for analog optical and microwave signals processing’ Nature Communications volume 16, Article number 5087 (2025)). The chip integrates high-speed modulators, optical filters, photodetectors and transfer-printed lasers, making it a compact, self-contained and programmable solution for high-frequency signal processing. This can replace bulky and power-hungry components, enabling faster wireless networks, low-cost microwave sensing, and scalable deployment in applications like 5G/6G, satellite communications, and radar systems.
As demand for higher data rates and operation at higher frequencies grows, new communications networks need much tighter integration between these high-speed fiber-optic links and wireless radio-frequency microwave transmission to overcome the struggle with signal processing complexity, high transmission losses, and power-hungry electronics. Microwave photonics offers a promising solution by using optical technology to process high-frequency signals with lower loss, higher bandwidth, and improved energy efficiency. However, most microwave photonics systems rely on bulky, fiber-based architectures that limit scalability. In contrast integrating microwave photonics onto a chip could enable more scalable and power-efficient systems, but early experimental demonstrations have either lacked key functionalities or required external components to achieve full performance.
imec and Ghent University now demonstrate a silicon photonic engine that processes and converts both optical and microwave signals on a single chip. The key innovation lies in the novel combination of a reconfigurable modulator and a programmable optical filter enabling efficient modulation and filtering of microwave signals while significantly reducing signal loss. This unique combination enhances overall performance, allowing the system to handle complex signal processing tasks with greater flexibility and efficiency for a wide range of applications.
The chip is fabricated on imec’s standard iSiPP50G silicon photonics platform, which includes low-loss waveguides and passive components, high-speed modulators and detectors, and thermo-optic phase shifters for tuning the optical response. To provide an integrated light source, the researchers incorporated an indium phosphide (InP) optical amplifier (developed by III-V Lab) on the chip using the microtransfer-printing technology developed at the Photonics Research Group (imec/Ghent University). In combination with on-chip tunable filter circuits, this allows the optical amplifier to function as a widely tunable laser, further enhancing the system’s versatility.
“The ability to integrate all essential microwave photonics components on a single chip marks a major step toward scalable and energy-efficient high-frequency signal processing,” says Wim Bogaerts, professor in the Photonics Research Group at Ghent University and imec. “By eliminating bulky external components, this technology paves the way for more compact, cost-effective solutions in next-generation wireless networks and advanced sensing systems.”
