News: Optoelectronics
2 September 2021
Tower and Quintessent partner to create foundry silicon photonics platform with integrated quantum dot laser
Specialty analog foundry Tower Semiconductor Ltd (which has fabrication plants in Migdal Haemek, Israel, and at its US subsidiaries in Newport Beach, CA and San Antonio, TX, and at TowerJazz Japan Ltd) and Quintessent of Santa Barbara, CA, USA, which specializes in laser integration with silicon photonic integrated circuits (PICs), are collaborating to create what they reckon will be the first silicon photonics (SiPho) process with integrated quantum dot lasers, addressing optical connectivity in artificial intelligence/machine learning (AI/ML) and disaggregated computing (data center) markets. According to market research firm Yole, the silicon photonics transceivers market for data centers is expected to rise rapidly at a compound annual growth rate (CAGR) of 40% to $3.5bn in 2025.
The new foundry process will build on Tower’s PH18 production silicon photonics platform and add Quintessent’s III-V quantum-dot-based lasers and optical amplifiers to enable a complete suite of active and passive silicon photonic elements. The resulting capability will be an industry first in demonstrating integrated optical gain in a standard foundry silicon photonics process, it is expected. The initial process development kit (PDK) should be available this year, with multi-project wafer runs (MPWs) following in 2022.
“I’m very excited by the prospects for a new class of high-performance lasers and photonic integrated circuits on silicon, leveraging the unique advantages of quantum dot materials,” says Dr John Bowers, UCSB professor and Quintessent co-founder.
The co-integration of lasers and amplifiers with silicon photonics at the circuit element level should improve overall power efficiency, eliminate traditional design constraints such as on-chip loss budgets, simplify packaging, and make possible new product architectures and functionalities. For example, a silicon photonic transceiver or sensor product with integrated lasers will be capable of complete self-test at the chip or wafer level. These advantages are further enhanced by employing semiconductor quantum dots as the active optical gain media, which enables devices with greater reliability, lower noise, and the ability to operate efficiently at higher temperatures.
“Bringing the III-V laser diode within our silicon photonics platform will enable single-chip photonic integrated circuit design,” says Tower executive director & fellow Dr David Howard. “This means that both III-V quantum dot amplifiers and lasers, and Tower’s silicon photonics passive and active elements, will be delivered by a foundry through a single MPW chip run,” he adds.
“We are pleased to combine our quantum dot gain functionality with Tower’s proven silicon photonics process to enable a disruptive new capability,” says Dr Alan Liu, co-founder & CEO of Quintessent. “This platform has great potential to solve the connectivity bottleneck limiting AI training systems and disaggregated computing, among other applications.”
The augmented PH18 process is part of DARPA’s ‘Lasers for Universal Microscale Optical Systems’ (LUMOS) program, which aims to bring high-performance lasers to advanced photonics platforms, addressing commercial and defense applications.
