Photonic Integration Group (PhI)

In the coming years, the generic foundry approach will cause a revolution in micro and nanophotonics, just as it did in microelectronics thirty years ago. So far, photonic integration processes have been developed for specific applications, and fully optimized to meet the specifications of those applications. As a result, there are almost as many integration processes as applications, and due to this huge fragmentation, their market is too small for return on investment. This is quite different from micro-electronics, where a huge market is served by a small number of generic integration processes, most of them CMOS.

The COBRA-PhI group is leading a paradigm shift in photonic integration by introducing the methodology which allowed microelectronics to change the world, in the field of photonics. We are working on a generic integration process in which a wide variety of optical chips is created from a small set of elementary optical building blocks: passive waveguides (for use in interconnection and passive devices like AWG-demultiplexers and MMI-couplers), and three basic building blocks for manipulating the phase, the amplitude and the polarization of the optical signal. We are leading the Joint European Platform for Photonic Integration of InP-based Components and Circuits (JePPIX), in which Europe’s key players in the fields of InP PIC manufacturing, Photonic CAD, equipment development, and technology R&D are cooperating in order to introduce a generic foundry model in photonics. This will reduce R&D and manufacturing costs by more than an order of magnitude, and will bring Photonic ICs within reach for many small and larger companies active in fields like telecommunications, data communications, health, metrology, sensing and security. We are presently coordinating a major European project (PARADIGM) with the aim of strengthening Europe’s lead in this field. Our generic integration process serves as a model for the foundry technology. We participate with research on advanced technology, library development for advanced components, novel methods for on-wafer testing, and design of advanced PICs. We are leading the “STW Perspective Program on Generic Technologies for Integrated Photonics” (GTIP). An important activity is our research on strongly improved process performance (smallest feature size, critical dimension control and reproducibility) using our unique 193-nm DUV lithography tool (ASML PAS5500/1100B).

As a major longer-term development we see the introduction of nanophotonic integration processes, in which a photonic layer is created in a thin high-index membrane, bound onto the top of a CMOS wafer. Today’s preferred membrane material is silicon, which supports compact integration of a full range of passive functionalities, with active functions like high-speed modulation and detection (Silicon Photonics). Heterogeneous integration of III-V layers is presently applied for providing the silicon circuits with the required gain for making lasers and optical amplifiers. Technologically this is challenging, however, and it is difficult to couple the light efficiently from the III-V layers to the silicon layer. We have chosen a different approach, in which we realize both active and passive functions in a thin InP Membrane On Silicon (IMOS), in which we create locally active regions with high gain. We have demonstrated a number of high-quality passive devices in this technology, and predict promising results for realization of active components. In the coming years we want to demonstrate that IMOS is capable of combining the best of Silicon Photonics and classical InP-based technology in a novel technology that will play a major role in tomorrow’s Photonic Integration.

We are working on reduction of laser dimensions in order to reduce the power consumption and increase the switching speed, by using metallic cavities for confinement of the light to volumes far below the diffraction limit. Back in 2007 we reported the smallest electrically pumped laser: a metallic nanocavity laser with a 200-nm diameter of the active region. In 2011, we reported the world’s first plasmonic DFB laser. Our research is focussed on integration of plasmonic lasers in IMOS technology, which will provide IMOS with a similar position in Photonics as CMOS in microelectronics.

For more information on Photonic Integration Group(PhI) please go to: http://www.tue.nl/universiteit/faculteiten/faculteit-electrical-engineering/onderzoek/onderzoeksprogrammas/photonic-integration-group-phi/