Co-Packaged Optics (CPO) Grating Coupling Solutions
2026-04-08
Grating Coupling in CPO Architecture
Grating Coupling is a pivotal interface technology within CPO (Co-Packaged Optics) architectures, responsible for efficiently guiding optical signals from the internal waveguides of a Silicon Photonics chip to external fibers.
In a CPO system, because the Silicon Photonics IC (SiPh IC) and the ASIC (Switch Chip) are tightly co-packaged, physical space is extremely limited. The Grating Coupler functions as a "vertical interconnect," utilizing microscopic grating structures on the silicon waveguide surface to vertically couple light beams in and out of the chip at a tilt angle of approximately 8° to 10° through the principle of diffraction.
Technical Advantages & Characteristics
Packaging Flexibility: Unlike Edge Coupling, which requires high-precision end-face polishing of the chip, grating coupling allows for testing and alignment at any location on the chip surface. This significantly enhances the convenience and efficiency of the packaging process.
High-Density Integration: It supports the direct connection of large-scale fiber arrays to the chip surface, meeting CPO’s stringent requirements for high bandwidth and ultra-compact form factors.
Grating Coupling is a pivotal interface technology within CPO (Co-Packaged Optics) architectures, responsible for efficiently guiding optical signals from the internal waveguides of a Silicon Photonics chip to external fibers.
In a CPO system, because the Silicon Photonics IC (SiPh IC) and the ASIC (Switch Chip) are tightly co-packaged, physical space is extremely limited. The Grating Coupler functions as a "vertical interconnect," utilizing microscopic grating structures on the silicon waveguide surface to vertically couple light beams in and out of the chip at a tilt angle of approximately 8° to 10° through the principle of diffraction.
Technical Advantages & Characteristics
Packaging Flexibility: Unlike Edge Coupling, which requires high-precision end-face polishing of the chip, grating coupling allows for testing and alignment at any location on the chip surface. This significantly enhances the convenience and efficiency of the packaging process.
High-Density Integration: It supports the direct connection of large-scale fiber arrays to the chip surface, meeting CPO’s stringent requirements for high bandwidth and ultra-compact form factors.
