Avicena and ams OSRAM Collaborate to Enhance Future Production of Ultra-Low Energy Chip-to-Chip Interconnects

Posted  by GoPhotonics


Avicena, a privately held company in Sunnyvale, CA, has partnered with ams OSRAM to develop high-volume manufacturing of GaN microLED arrays for its industry-leading LightBundle™ communication architecture. Avicena exhibited its LightBundle™ architecture and technology at the OFC 2023.

The need for next-generation computing power is here, driven by strong AI/ML and HPC application demand – for products like ChatGPT, DALL-E, autonomous vehicle training, and many others. Attempts to scale current architectures are running headlong into physical limits leading to slower throughput growth, power-hungry and hard-to-cool systems.

The Avicena LightBundle architecture breaks new ground by unlocking the performance of xPUs, memory and sensors – removing key constraints of bandwidth and proximity while simultaneously offering an order-of-magnitude reduction in power consumption.

LightBundle™ is based on arrays of innovative GaN LED micro-emitters that can be integrated onto high performance CMOS ICs. This leverages emerging microLED manufacturing ecosystems, in which ams OSRAM is a major player.

We acquired our fab from Nanosys in October to accelerate our development efforts and support low-volume prototype manufacturing,” said Bardia Pezeshki, founder and CEO of Avicena. “However, we are addressing very sizeable markets requiring high-volume manufacturing. We are very pleased to partner with one of world’s top GaN LED companies to provide a path to satisfy the expected high volumes required by our customers, including hyperscale datacenter operators and the world’s leading IC companies.” 

Avicena’s LightBundle technology provides an opportunity for GaN microLEDs to impact numerous key applications including HPC, AI/ML, sensors, automotive and aerospace,” said Robert Feurle, Executive Vice President and Managing Director, OS Business Unit at ams OSRAM. “As a global leader in GaN LEDs, we are excited to partner with Avicena to transform these very large and important markets.”

About the Technology

Today’s high-performance ICs use SerDes-based electrical links to achieve adequate IO density. However, the power consumption and bandwidth density of these electrical links degrade quickly with length. Conventional optical communications technologies developed for networking applications have been impractical for inter-processor and processor-memory interconnects due to their low bandwidth density, high power consumption, and high cost. Moreover, co-packaging existing laser sources with hot ASICs does not fit well for reliability reasons unless external laser sources (ELS) are used which increases complexity and cost.

Avicena’s LightBundle links use densely packed arrays of GaN microLEDs to create highly parallel optical interconnects with typical throughputs of > 1Tb/s at energies of < 1 pJ/bit. A LightBundle cable uses a highly multicore multimode fiber to connect a GaN microLED transmitter array to a matching array of silicon photodetectors (PDs). Arrays of hundreds or thousands of LightBundle’s microLEDs and PDs are easily integrated with standard CMOS ICs, enabling the closest integration of optical interconnects with electrical circuits. In addition to high energy efficiency and high bandwidth density, these LightBundle links also exhibit low latency since the modulation format of the individual links is simple NRZ instead of PAM4 which is common in many modern optical links but has the disadvantage of higher power consumption and additional latency. 

The parallel nature of LightBundle™ is well matched to parallel chiplet interfaces like UCIe, OpenHBI, and BoW, and can also be used to extend the reach of compute interconnects like PCIe/CXL, HBM/DDR/GDDR memory links, as well as various inter-processor interconnects like NVLink with low power and low latency.

Click here to know more about microLED-based LightBundle chip-to-chip interconnects.