Heterogeneous integration of III-V materials onto silicon photonics has experienced enormous progress in the last few years, setting the groundwork for the implementation of complex on-chip optical systems that go beyond single device performance. Recent advances on the field are expected to impact on next generation optical communications to attain low power, high efficiency and portable solutions. To accomplish that aim, intense research on hybrid lasers, modulators and photodetectors is being done to implement optical modules and photonic integrated networks with specifications that match the market demands. Similarly, important advances on packaging and thermal management of hybrid photonic integrated circuits (PICs) is currently in progress. In this paper, we report our latest results on hybrid III-V on Si transmitters, receivers and packaged optical modules for high-speed optical communications. In addition, a review of recent advances in this field will be provided for benchmarking purposes.
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.
With metal stripes being intrinsic components of plasmonic waveguides, plasmonics provides a “naturally” energy-efficient platform for merging broadband optical links with intelligent electronic processing, instigating a great promise for low-power and small-footprint active functional circuitry. The first active Dielectric-Loaded Surface Plasmon Polariton (DLSPP) thermo-optic (TO) switches with successful performance in single-channel 10 Gb/s data traffic environments have led the inroad towards bringing low-power active plasmonics in practical traffic applications. In this article, we introduce active plasmonics into Wavelength Division Multiplexed (WDM) switching applications, using the smallest TO DLSPP-based Mach-Zehnder interferometric switch reported so far and showing its successful performance in 4×10 Gb/s low-power and fast switching operation. The demonstration of the WDM-enabling characteristics of active plasmonic circuits with an ultra-low power × response time product represents a crucial milestone in the development of active plasmonics towards real telecom and datacom applications, where low-energy and fast TO operation with small-size circuitry is targeted.
11 March 2019 in IEEE Journal of Selected Topics in Quantum Electronics
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.
Surface plasmon propagating modes supported by metal/dielectric interfaces in various configurations can be used for radiation guiding similarly to conventional dielectric waveguides. Plasmonic waveguides offer two attractive features: subdiffraction mode confinement and the presence of conducting elements at the mode‐field maximum. The first feature can be exploited to realize ultrahigh density of nanophotonics components, whereas the second feature enables the development of dynamic components controlling the plasmon propagation with ultralow signals, minimizing heat dissipation in switching elements. While the first feature is yet to be brought close to the domain of practical applications because of high propagation losses, the second one is already being investigated for bringing down power requirements in optical communication systems. In this review, the latest application‐oriented research on radiation modulation and routing using thermo‐optic dielectric‐loaded plasmonic waveguide components integrated with silicon‐based photonic waveguides is overviewed. Their employment under conditions of real telecommunications is addressed, highlighting challenges and perspectives.
We report on the design, fabrication and performance of a hetero-integrated III-V on silicon distributed feedback lasers (DFB) at 1310 nm based on direct bonding and adiabatic coupling. The continuous wave (CW) regime is achieved up to 55 °C as well as mode-hop-free operation with side-mode suppression ratio (SMSR) above 55 dB. At room temperature, the current threshold is 36 mA and the maximum coupled power in the silicon waveguide is 22 mW.