A Photonic Chip Package with Edge Fiber Connections

This patent describes a compact package for a photonic chip that integrates electrical components and short optical fibers, allowing direct connection to external optical cables from the side.

What it covers

This patent describes a special package for a photonic integrated circuit (PIC), which is a chip that uses light. The package includes an `overmold body` that protects the main `PIC die` and other `ancillary devices` like amplifiers. Inside, short `optical fiber stubs` are connected to the PIC die's `optical waveguide system` (Claim 1). These stubs extend to the side of the package, forming an `edge fiber coupling interface` (Claim 1). This interface allows external optical fibers to connect using a `connector`, either by having the stubs `protrude` (Claim 2) or be `flush` (Claim 4) with the package's side. Electrical connections for the PIC die and ancillary devices are handled by a `redistribution wiring layer (RDL) interposer` and a `ball grid array (BGA)` for attaching to a circuit board (Claim 1). For example, this package could allow a high-speed data center switch to easily plug into fiber optic cables directly from the side of its chip module.

What it doesn't cover

• —Does not cover packages where optical fibers connect from the top or bottom surfaces, only the 'lateral side' (Claim 1).
• —Does not cover packages without an 'overmold body' protecting the components (Claim 1).
• —Does not cover packages that lack both a 'redistribution wiring layer (RDL) interposer' and a 'ball grid array (BGA)' for electrical connections (Claim 1).
• —Does not cover packages where the optical fiber stubs are not 'operatively coupled to the optical waveguide system' of the PIC die (Claim 1).
• —Does not cover packages that do not include an 'ancillary device' alongside the PIC die (Claim 1).

The clever bit

The novelty lies in integrating the optical fiber stubs, the photonic chip, electrical ancillary devices, and electrical connections (RDL and BGA) into a single overmolded package with a specific `edge fiber coupling interface`. This design allows for direct, robust, and compact optical connections from the side of the package, simplifying manufacturing and system integration.

Why it matters

This packaging method is important for making photonic chips more practical and easier to integrate into electronic systems. By combining optical and electrical components in one compact package with a standardized edge connection, it simplifies assembly and improves reliability for high-speed data transfer. This approach helps reduce the physical size and cost of optical transceivers, which are critical for modern data centers and telecommunications networks.

Real-world examples

• 1.Optical transceivers for data centers
• 2.High-speed network interface cards
• 3.Fiber-optic communication modules
• 4.Photonic sensor packages