Offering open-access silicon photonics-based technologies has played a pivotal role in unleashing this technology from research laboratories to industry. Fabless enterprises rely on the open-access of these technologies for their product development. In the last decade, a diverse set of open-access technologies with medium and high technology readiness levels have emerged. This paper provides a review of the open-access silicon and silicon nitride photonic IC technologies offered by the pilot lines of European research institutes and companies. The paper also highlights upcoming features of these platforms and discusses how they address the long-term market needs.

Silicon photonics is one of the most prominent technology platforms for integrated photonics and can support a wide variety of applications. As we move towards a mature industrial core technology, we present the integration of silicon nitride (SiN) material to extend the capabilities of our silicon photonics platform. Depending on the application being targeted, we have developed several integration strategies for the incorporation of SiN. We present these processes, as well as key components for dedicated applications. In particular, we present the use of SiN for athermal multiplexing in optical transceivers for datacom applications, the nonlinear generation of frequency combs in SiN micro-resonators for ultra-high data rate transmission, spectroscopy or metrology applications and the use of SiN to realize optical phased arrays in the 800–1000 nm wavelength range for Light Detection And Ranging (LIDAR) applications. These functionalities are demonstrated using a 200 mm complementary metal-oxide-semiconductor (CMOS)-compatible pilot line, showing the versatility and scalability of the Si-SiN platform.

In this paper we present the hybrid III-V/Si photonic platform developed in CEA-LETI. The overall integration is done in a fully CMOS compatible 200mm technology, scalable to 300mm wafers, leveraging the large scale integration capabilities of silicon photonics. III-V material is integrated on top of a mature silicon photonic front-end wafer through direct molecular bonding enabling the monolithic integration of light sources. DFB and DBR laser reference designs are used as test vehicules for the process validation. A modular approach is used in order to minimize the impact on the already qualified silicon-based devices. Collective III-V die bonding is proposed in this platform. CMOS compatible metallizations are used to form ohmic contact on n-InP and P-InGaAs leading to contact resistivity in the range of $10^{-6}\Omega$ .cm2. A planarized 2-metal level BEOL is used to connect the device, leading to a drastic reduction of series resistance. Finally, the funcitonnality of both types of lasers is demonstrated with SMSR up to 50dB and maximum output power of 5mW.

We report ultra-low propagation losses in silicon sub-micrometric waveguides on a 200 mm CMOS compatible photonics platform. We show median losses in C-band (O-band) as low as 0.1dB/cm and 0.7dB/cm (0.14dB/cm and 1.1dB/cm) in monomode rib and strip waveguides, respectively, thanks to a H2 smoothing annealing. In addition to the significant loss reduction, we show that the performance characteristic of the main passive and active components of the photonics platform are preserved or even improved by the smoothing process.

Subwavelength grating (SWG) metamaterials have garnered a great interest for their singular capability to shape the material properties and the propagation of light, allowing the realization of devices with unprecedented performance. However, practical SWG implementations are limited by fabrication constraints, such as minimum feature size, that restrict the available design space or compromise compatibility with high-volume fabrication technologies. Indeed, most successful SWG realizations so far relied on electron-beam lithographic techniques, compromising the scalability of the approach. Here, we report the experimental demonstration of an SWG metamaterial engineered beam splitter fabricated with deep-ultraviolet immersion lithography in a 300-mm silicon-on-insulator technology. The metamaterial beam splitter exhibits high performance over a measured bandwidth exceeding 186 nm centered at 1550 nm. These results open a new route for the development of scalable silicon photonic circuits exploiting flexible metamaterial engineering.

Fast, low-noise and sensitive avalanche photo-receivers are needed for surging short-reach photonic applications. Limitations concerning bandwidth, throughput and energy consumption should be overcome. In this work, we comprehensively study the performance opportunities provided by avalanche p-i-n photodetectors with lateral silicon-germanium-silicon heterojunctions. Our aim is to circumvent the need for chip-bonded electronic amplifiers. In particular, we demonstrate that avalanche photodetectors based on silicon-germanium-silicon heterostructures yield reliable opto-electrical performances, with high gain-bandwidth products up to 480 GHz and low effective ionization ratios down to 0.15. Moreover, they improve power sensitivities for high-speed optical signals and have a low energy dissipation of only a few fJ per received information bit. These results pave the way for high-performing receivers for energy-aware data links, in next-generation short-distance data communications.