As photonic integrated circuits (PIC) begins to garner growing attention in light of its vast potential in data centers, telecommunications and automotive, the technology has also emerged as the overarching theme of Dutch-Taiwan semiconductor cooperations.
On the eve of SEMICON Taiwan, a Dutch innovation mission focusing on integrated photonics and advanced packaging has arrived in Taiwan, with delegates from various key players in the Dutch photonics ecosystem, including PhotonDelta, a Eindhoven-based growth accelerator for the photonic chip industry, SmartPhotonics, a foundry offering development and production services for indium phosphide (InP) based PICs, and PHIX, which provides assembly and packaging service for PICs. Among the delegates are also representatives of various leading research institutions, such as University of Technology in Eindhoven, University of Twente, Chip Integration Technology Center (CITC), and Photonic Integration Technology Center (PITC).
Silicon-based photonic IC platform, commonly known as silicon photonics (SiPh), has become one of the main highlights of the cooperation, given its compatibility to the CMOS process for volume production. Thanks to SiPh's vast potential in data centers, telecommunications, and other sectors, by 2025 the market for SiPh is expected to reach US$3.9 billion, according to the research firm Yole. Among them, data center transceivers will account for US$3.6 billion, while long-haul transceivers, 5G transceivers, and automotive LiDAR will account for US$186 million, US$61 million, and US$44 million, respectively.
Laurens Weers, CFO of PhotonDelta, pointed out that the Netherlands has long been engaged in the PIC industry, with fundamental research and academic collaborations traced back to the 1970s. When it comes to InP-based and silicon nitride (SiN)-based photonic chips, Weers noted that the Netherlands is among the global top three in research publications. "We share the same godfather with TSMC, as Philips was very advanced in InP development, with decades of relevant R&D work," the PhotonDelta CFO told DIGITIMES Asia.
Above all, the country has the largest concentration of companies working on PIC technology. In 2022, PhotonDelta itself was awarded EUR1.1 billion by the Netherlands' National Growth Fund to further strengthen its PIC position.
There's no dominant platform for integrated photonics
Though silicon photonics technology, in terms of cost and production processes, is a little more mature and CMOS-compatible, Weers believes that there won't be a dominant platform for PIC, because all have different advantages. "It's going to be a mix and match driven by different applications," he observed, indicating that SiPh does not deliver all the required functionalities on a single chip. For example, as silicon is not a direct bandgap material, it cannot emit light and can't serve as a laser source. "If you want an active laser, you will have to come up with a different solution, and I think InP is a good fit - as it is a light source in its own right," Weers pointed out.
Nevertheless, as major foundry players like TSMC, Intel and GlobalFoundries have all introduced their silicon photonics platforms, Weers sees it as a great opportunity for the Dutch ecosystem to pursue further integration with them, noting that PhotonDelta is also working closely with Imec to integrate its technology platforms with silicon photonics. "For PhotonDelta, the current focus is basically maturing the supply chain, to further industrialize it," said Weers. "Therefore, it's important to join forces with the leading players in the semiconductor industry to leverage their expertise in scaling up production and both in frontend and backend." Referring to collaboration with Taiwan, apart from the assistance to move from prototyping to volume production, the PhotonDelta CFO also drew attention to the importance of building PDK libraries with world-class building blocks, so as to ensure that many applications are more accessible, especially to startups.
Albert Hasper, CEO of PHIX, also sees that InP-based and SiN-based PIC platforms will work in conjunction with Si-based platforms. "What we see is silicon photonics, but also in combination with SiN and InP platforms. So we call it hybrid or heterogeneous assembly: the trend is that different platforms are being co-packaged in one package," said Hasper. Unlike in the mainstream silicon-based semiconductor world where a single platform dominates, different platforms are needed when it comes to photonics , as the applications of these SiPh chips are different such as in biosensors and transceivers, according to the PHIX CEO.
Packaging critical to a reliable supply chain
Founded in 2017, PHIX specializes in hybrid PIC assembly and fiber array interfacing. From a backend perspective, Hasper sees the main challenge of the PIC industry in setting up a complete and reliable ecosystem from design to package, in addition to having enough volume. "We can see that the PICs are still under development and the volume remains low, and our customers cannot rely on a reliable chip supply chain," observed Hasper, adding that the same holds for the design kits that are also immature. "The whole ecosystem should mature itself to a level that our customers can really count on."
Though the European Chips Act marks a milestone, Hasper believes that it is primarily earmarked towards frontend process, even though there's also a gap in packaging in the supply chain as backend capacity remains concentrated in Asia. "Even with TSMC in Europe, the supply chain is not complete, because without packaging, you have nothing," remarked the chief executive, observing that there has been increasing attention for packaging as its complexity dramatically increases.
"Heterogeneous packaging will clearly be on the agenda of the bigger packaging firms like ASE, Amkor and all these big players," indicated Hasper. "I think if they want to also do photonic packaging, what we have developed is also needed for that, and then there will also be cooperation together." The most complicated thing, according to Hasper, is to transfer from medium-volume to high-volume production, and there exists a lot of room for cooperation with Taiwan in this area.
"We are well aware that we cannot be independent on our own, and we need international collaboration with Taiwan, and with the rest of the world, to get the industry mature and going," the PHIX CEO pointed out, adding that PHIX would like to see how the photonics infrastructure in Taiwan is developing and work with Taiwan's customers.