(Invited) Advanced III-V-on-Si Heterogeneously Integrated Platforms for Next Generation Silicon Photonics Integrated Circuits

The field of Silicon Photonics has experienced a solid and continuous progress over the last few years, gaining in technological maturity, design tools, and new methods [1]. The deployment of low-cost, compact, and power-efficient photonic circuits with a high wafer yield and robustness stands as one of the fundamental pillars that sustain such progress [2]. Presently, photonic circuit technology has diversified its number of available platforms. Despite the fact that indium phosphide (InP) [3] and silicon-on-insulator (SOI) platforms are still considered as the workhorses of integrated photonics in terms of maturity and deployment of active (InP) and passive (SOI) components, other alternatives such as germanium-on-silicon [4], silicon nitride-on-insulator [2] or hybrid solutions combining different functional materials with Si are gaining momentum [5]. A representative example is the heterogeneous III-V/Si platform [6], which has been used to develop compact photonic circuits with on-chip gain. Contrarily to the hybrid integration, the III-V-on-Si heterogeneous integration avoids the constraints of chip-to-chip alignment while enabling the simultaneous integration of hundreds of III-V gain chips in a scalable fashion. Still, the integration methods of such III-V materials on silicon need to be improved to attain the maturity level of the monolithic III-V platform, which benefits from a complete palette of technological solutions not yet available in the III-V-on-Si heterogeneous integration. More recently, an advanced heterogeneous scheme based on wafer-seed-bonding and epitaxial regrowth has emerged [7]–[9]. The ambition is to create a generic integration scheme combining the best offered by the III-V and the Si-photonics platforms. The regrowth capability gives access to the large epitaxial toolkit available in the conventional InP monolithic platform, where several epitaxial steps are often implemented [10][11]. To cite some of them, the epitaxial regrowth of III-V materials to bury III-V lasers bonded onto silicon are object of intense research nowadays to overcome the thermally inefficient buried oxide [12]. In this paper, we will review the advances on III-V-on-Si heterogeneous integration through the implementation of several key demonstrators and building blocks for silicon photonics, including on-chip semiconductor optical amplifiers, lasers and electro-absorption modulators. We will discuss the progress and benefits of the direct seed bonding and regrowth as well as new device designs to improve the performance. References: [1] D. Thomson et al. , “Roadmap on silicon photonics,” J. Opt. , vol. 18, no. 7, p. 73003, 2016, doi: 10.1088/2040-8978/18/7/073003. [2] S. Y. Siew et al. , “Review of Silicon Photonics Technology and Platform Development,” Journal of Lightwave Technology , vol. 39, no. 13. Institute of Electrical and Electronics Engineers Inc., pp. 4374–4389, Jul. 01, 2021, doi: 10.1109/JLT.2021.3066203. [3] M. Smit, K. Williams, and J. Van Der Tol, “Past, present, and future of InP-based photonic integration,” APL Photonics , vol. 4, no. 5, May 2019, doi: 10.1063/1.5087862. [4] J. Chrétien et al. , “GeSn Lasers Covering a Wide Wavelength Range Thanks to Uniaxial Tensile Strain,” ACS Photonics , vol. 6, no. 10, pp. 2462–2469, Oct. 2019, doi: 10.1021/acsphotonics.9b00712. [5] S. Lin et al. , “Efficient, tunable flip-chip-integrated III-V/Si hybrid external-cavity laser array,” Opt. Express , vol. 24, no. 19, p. 21454, Sep. 2016, doi: 10.1364/oe.24.021454. [6] D. Liang and J. E. Bowers, “Recent Progress in Heterogeneous III-V-on-Silicon Photonic Integration,” Light Adv. Manuf. , vol. 2, no. 1, pp. 1–25, 2021, doi: 10.37188/lam.2021.005. [7] K. Takeda, S. Matsuo, T. Fujii, K. Hasebe, T. Sato, and T. Kakitsuka, “Epitaxial growth of InP to bury directly bonded thin active layer on SiO2/Si substrate for fabricating distributed feedback lasers on silicon,” IET Optoelectron. , vol. 9, no. 4, pp. 151–157, 2015, doi: 10.1049/iet-opt.2014.0138. [8] C. Besancon et al. , “AlGaInAs Multi-quantum Well Lasers On Silicon-on-insulator Photonic Integrated Circuits Based On InP-seed-bonding And Epitaxial Regrowth,” Appl. Sci. , vol. 12, no. 1, Jan. 2022, doi: 10.3390/app12010263. [9] Y. Hi et al. , “Electrically-Pumped 1.31 μm MQW Lasers by Direct Epitaxy on Wafer-Bonded InP-on-SOI Substrate,” in Proceedings of 2018 IEEE Photonics Conference (IPC) , 2018, pp. 1–2. [10] V. Rustichelli et al. , “Monolithic integration of buried-heterostructures in a generic integrated photonic foundry process,” IEEE J. Sel. Top. Quantum Electron. , vol. 25, no. 5, Sep. 2019, doi: 10.1109/JSTQE.2019.2927576. [11] F. Lemaître et al. , “96 nm Extended Range Laser Source Using Selective Area Growth,” in European Conference on Optical Communication, ECOC , 2018, doi: 10.1109/ECOC.2018.8535218. [12] C. Besancon et al. , “AlGaInAs Multi-Quantum Well Laser on Silicon Achieved byDirect-Bonding and MOVPE Semi-Insulating Buried Heterostructure Regrowth,” in Compound Semiconductor Week 2023 , Jan. 2023, vol. 12, no. 1, doi: 10.3390/app12010263.