Wafer-level vacuum sealing for packaging of silicon photonic MEMS

Silicon (Si) photonic micro-electro-mechanical systems (MEMS), with its low-power phase shifters and tunable couplers, is emerging as a promising technology for large-scale reconfigurable photonics with potential applications for example in photonic accelerators for artificial intelligence (AI) workloads. For silicon photonic MEMS devices, hermetic/vacuum packaging is crucial to the performance and longevity, and to protect the photonic devices from contamination. Here, we demonstrate a wafer-level vacuum packaging approach to hermetically seal Si photonic MEMS wafers produced in the iSiPP50G Si photonics foundry platform of IMEC. The packaging approach consists of transfer bonding and sealing the silicon photonic MEMS devices with 30 μm-thick Si caps, which were prefabricated on a 100 mm-diameter silicon-on-insulator (SOI) wafer. The packaging process achieved successful wafer-scale vacuum sealing of various photonic devices. The functionality of photonic MEMS after the hermetic/vacuum packaging was confirmed. Thus, the demonstrated thin Si cap packaging shows the possibility of a novel vacuum sealing method for MEMS integrated in standard Si photonics platforms

MORPHIC : programmable photonic circuits enabled by silicon photonic MEMS

In the European project MORPHIC we develop a platform for programmable silicon photonic circuits enabled by waveguide-integrated micro-electro-mechanical systems (MEMS). MEMS can add compact, and low-power phase shifters and couplers to an established silicon photonics platform with high-speed modulators and detectors. This MEMS technology is used for a new class of programmable photonic circuits, that can be reconfigured using electronics and software, consisting of large interconnected meshes of phase shifters and couplers. MORPHIC is also developing the packaging and driver electronics interfacing schemes for such large circuits, creating a supply chain for rapid prototyping new photonic chip concepts. These will be demonstrated in different applications, such as switching, beamforming and microwave photonics