OpenLight's CEO on its silicon photonics strategy

Adam Carter, recently appointed the CEO of OpenLight, discusses the company’s strategy and the market opportunities for silicon photonics.

Adam Carter, CEO of OpenLight

Adam Carter’s path to becoming OpenLight’s first CEO is a circuitous one.

OpenLight, a start-up, offers the marketplace an open silicon photonics platform with integrated lasers and gain blocks.

Having worked at Cisco and Oclaro, which was acquired by Lumentum in 2018, Carter decided to take six months off. Covid then hit, prolonging his time out.

Carter returned as a consultant working with firms, including a venture capitalist (VC). The VC alerted him about OpenLight’s search for a CEO.

Carter’s interest in OpenLight was immediate. He already knew the technology and OpenLight’s engineering team and recognised the platform’s market potential.

“If it works in the way I think it can work, it [the platform] could be very interesting for many companies who don't have access to the [silicon photonics] technology,” says Carter.

Offerings and strategy

OpenLight’s silicon photonics technology originated at Aurrion, a fabless silicon photonics start-up from the University of California, Santa Barbara.

Aurrion’s heterogeneous integration silicon photonics technology included III-V materials, enabling lasers to be part of the photonic integrated circuit (PIC).

Juniper Networks bought Aurrion in 2016 and, in 2022, spun out the unit that became OpenLight, with Synopsys joining Juniper in backing the start-up.

OpenLight offers companies two services.

The first is design services for firms with no silicon photonics design expertise. OpenLight will develop a silicon photonics chip to meet the company’s specifications and take the design to production.

“If you don't have a silicon photonics design team, we will do reference architectures for you,” says Carter.

The design is passed to Tower Semiconductor, a silicon photonics foundry that OpenLight, and before that, Juniper, worked with. Chip prototype runs are wafer-level tested and passed to the customer.

OpenLight gives the company the Graphic Data Stream (GDS) file, which defines the mask set the company orders from Tower for the PIC’s production.

OpenLight also serves companies with in-house silicon photonics expertise that until now have not had access to a silicon photonics process with active components: lasers, semiconductor optical amplifiers (SOAs), and modulators.

The components are part of the process design kit (PDK), the set of files that models a foundry’s fabrication process. A company can choose a PDK that best suits its silicon photonics design for the foundry to then make the device.

OpenLight offers two PDKs via Tower Semiconductor: a Synopsys PDK and one from Luceda Photonics.

OpenLight does not make components, but offers reference designs. OpenLight gets a small royalty with every wafer shipped when a company’s design goes to production.

“They [Tower] handle the purchasing orders, the shipments, and if required, they'll send it to the test house to produce known good die on each wafer,” says Carter

OpenLight plans to expand the foundries it works with. “You have to give customers the maximum choice,” says Carter.

Design focus

OpenLight’s design team continues to add components to its library.

At the OFC show in March, held in San Diego, OpenLight announced a 224-gigabit indium phosphide optical modulator to enable 200-gigabit optical lanes. OpenLight also demoed an eight-by-100-gigabit transmitter alongside Synopsys’s 112-gigabit serialiser-deserialiser (serdes).

OpenLight also offers a ‘PDK sampler’ for firms to gain confidence in its process and designs.

The sampler comes with two PICs. One PIC has every component offered in OpenLight’s PDK so a customer can probe and compare test results with the simulation models of Tower’s PDKs.

”You can get confidence that the process and the design are stable,” says Carter.

The second PIC is the eight by 100 gigabit DR8 design demoed at OFC.

The company is also working on different laser structures to improve the picojoule-per-bit performance of its existing design.

“Three picojoules per bit will be the benchmark, and it will go lower as we understand more about reducing these numbers through design and process,” says Carter.

The company wants to offer the most updated components via its PDK, says Carter.

OpenLight’s small design team can’t do everything at once, he says: “And if I have to license other people’s designs into my PDK, I will, to make sure my customer has a maximum choice.”

Market opportunities

OpenLight’s primary market focus is communications, an established and significant market that will continue to grow in the coming years.

To that can be added artificial intelligence (AI) and machine learning, memory, and high-speed computing, says Carter.

“If you listen to companies like Google, Meta, and Amazon, what they're saying is that most of their investment in hardware is going into what is needed to support AI and machine learning,” says Carter. “There is a race going on right now.”

When AI and machine learning take off, the volumes of optical connections will grow considerably since the interfaces will not just be for networking but also computing, storage, and memory.

“The industry is not quite ready yet to do that ramp at the bandwidths and the densities needed,” he says, but this will be needed in three to four years.

Large contract manufacturers also see volumes coming and are looking at how to offer optical subassembly, he says.

Another market opportunity is telecoms and, in particular coherent optics for metro networks. However, unit volumes will be critical. “Because I am in a foundry, at scale, I have to fill it with wafers,” says Carter.

Simpler coherent designs - 'coherent lite' - connecting data centre buildings could be helpful. There is much interest in short-reach connections, for 10km distances, at 1.6 terabit or higher capacity where coherent could be important and deliver large volumes, he says.

Emerging markets for OpenLight’s platform include lidar, where OpenLight is seeing interest, high-performance computing, and healthcare.

“Lidar is different as it is not standardised,” he says. It is a lucrative market, given how the industry has been funded.

OpenLight wants to offer lidar companies early access to components that they need. Many of these companies have silicon photonics design teams but may not have the actives needed for next-generation products, he says.

“I have a thesis that says everywhere a long-wavelength single-mode laser goes is potential for a PIC,” says Carter

Healthcare opportunities include a monitoring PIC placed on a person’s wrist. Carter also cites machine vision, and cell phone makers who want improved camera depth perception in handsets.

Carter is excited by these emerging silicon photonics markets that promise new incremental revenue streams. But timing will be key.

“We have to get into the right market at the right time with the right product,” says Carter. “If we can do that, then there are opportunities to grow and not rely on one market segment.”

As CEO, how does he view success at OpenLight?

“The employees here, some of whom have been here since the start of Aurrion, have never experienced commercial success,” says Carter. “If that happens, and I think it will because that is why I joined, that would be something I could be proud of.”