Copackaged Optics for High Speed and Efficient Data Transfer

Copackaged optics represents a fundamental shift in how data centres manage bandwidth at the switch level. By placing optical engines directly onto the switch ASIC package, this architecture eliminates the pluggable transceiver modules that have constrained power efficiency and port density for over a decade. The technology addresses a bottleneck that conventional electrical interconnects cannot solve as data rates push beyond 800 Gbps per port. Engineers at major semiconductor firms now treat this integration as a prerequisite for next-generation networking hardware.

How Copackaged Optics Works

Traditional switch architectures route electrical signals from the ASIC through circuit board traces to front-panel pluggable modules. Each conversion between electrical and optical domains consumes power and introduces latency. Co-packaged optical systems integrate photonic chiplets within millimetres of the switch die, shortening the electrical path to under 10 mm. This proximity reduces signal attenuation and eliminates the need for power-hungry retimers that currently populate high-speed switch boards.

Bandwidth Density Improvements

A single switch ASIC supporting 51.2 Tbps throughput requires 64 ports at 800 Gbps each. Pluggable modules at this density demand front-panel space that physically does not exist in standard 1U rack units. Optical engines integrated into the package substrate solve this constraint by moving the electro-optical conversion off the front panel entirely. The result is a 3x improvement in bandwidth per rack unit compared to pluggable architectures. Data centre operators gain the ability to scale network capacity without expanding their physical footprint, a critical advantage when rack space in colocation facilities costs upwards of USD 1,500 per month.

Power Efficiency Gains

Pluggable transceivers consume between 12 and 15 watts per 800 Gbps module. Copackaged optics reduces this figure to approximately 5 watts per 800 Gbps channel by eliminating retimers, shortening trace lengths, and operating photonic components at optimised bias points. For a hyperscale data centre running 100,000 switch ports, this translates to a power saving of roughly 700 kilowatts. Cooling infrastructure costs drop proportionally, compounding the operational savings over the 5 to 7 year lifecycle of deployed networking equipment.

Precision Manufacturing Requirements

The performance of co-packaged optical engines depends on manufacturing tolerances that sit at the boundary of current production capability. Fibre alignment to silicon photonic waveguides requires positional accuracy within 0.5 microns. Substrate warpage must stay below 25 microns across a 50 mm package to prevent fibre coupling losses. These specifications demand equipment calibrated daily and operators trained in sub-micron assembly techniques.

Substrate and Interposer Fabrication

Silicon photonic interposers carry optical waveguides alongside electrical redistribution layers. AMT manufactures the precision mechanical components that support these assemblies, including alignment fixtures, fibre array connectors, and thermal interface structures. Each fixture undergoes coordinate measuring machine inspection to verify flatness, parallelism, and hole position accuracy before release to production.

• Fibre V-groove arrays machined to positional tolerances of plus or minus 0.3 microns
• Alignment pin assemblies with diameter tolerances held to plus or minus 1 micron
• Thermal spreader plates lapped to surface flatness below 2 microns across 30 mm spans
• Hermetic seal frames for protecting photonic chiplets from moisture ingress

Thermal Management Challenges

Optical engines generate concentrated heat loads within the switch package. Junction temperatures above 85 degrees Celsius degrade laser performance and shorten component lifetimes. AMT produces copper-tungsten heat spreaders and micro-channel cold plates that manage thermal densities exceeding 100 watts per square centimetre. The company machines cooling channels with widths as narrow as 200 microns, maintaining consistent cross-sections across channel lengths of 25 mm. Thermal simulation data guides each design, ensuring that heat flux paths remain predictable under variable workload conditions.

“Singapore has built a strong ecosystem for photonics manufacturing, with over 30 companies active in the sector and research institutes providing deep technical support,” said Mr. Chang Chin Nam, Senior Vice President at the Agency for Science, Technology and Research (A*STAR). “The convergence of semiconductor packaging and optical integration creates opportunities for precision manufacturers with the right capabilities.”

Industry Adoption and Market Trajectory

Broadcom, NVIDIA, and Intel have each demonstrated co-packaged optical switch prototypes at major industry conferences between 2024 and 2026. Commercial deployments are expected to begin at hyperscale data centres during 2027, with broader adoption following as the supply chain matures. Market analysts project the segment will reach USD 4.2 billion by 2030, growing at a compound annual rate of 38%. This growth trajectory reflects the urgent need for bandwidth scaling that pluggable architectures simply cannot deliver.

The transition creates demand for new categories of precision components. Fibre management structures, optical bench substrates, and hermetic packages all require machining and assembly capabilities that differ from conventional transceiver manufacturing. Companies positioned at the intersection of precision mechanical engineering and photonic packaging stand to capture meaningful share of this emerging market.

Quality and Testing Protocols

Every optical alignment component undergoes interferometric surface measurement and automated dimensional inspection before shipment. AMT employs white-light interferometry to map surface topography at nanometre resolution, identifying defects invisible to conventional optical microscopy. Incoming fibre arrays receive 100% insertion loss testing to verify coupling efficiency meets specification. Rejected parts enter a formal non-conformance review process where root cause analysis feeds back into process improvements.

The path forward for data centre interconnects runs through integrated optical packaging solutions that reduce power consumption while scaling bandwidth, and precision manufacturing of copackaged optics components forms the foundation that makes this transition achievable at production scale.