Korean researchers have developed the nation's first 200Gbps photodetector device for use in large-scale AI data centers and 5G/6G mobile communication infrastructure.
The technology enables ultra-high-speed data reception capable of transmitting five full HD movies of 5GB each in just one second.
The Electronics and Telecommunications Research Institute (ETRI) announced on the 19th that it has developed a photodetector device capable of processing optical signals at 200Gbps per channel.
Photodetectors are essential semiconductor components that convert optical signals into electrical signals, determining the data reception performance of data centers and communication networks.
The photodetector developed by the research team achieves bandwidth exceeding 70GHz and high optical responsivity above 0.75A/W simultaneously, with dimensions of 0.5mm × 0.4mm. The device features a "back-side lens integrated structure" with a convex lens made of indium phosphide (InP) monolithically integrated on the chip's back side, significantly improving optical reception efficiency and alignment convenience. The entire process from design to fabrication was accomplished using purely domestic technology.
The device is planned for application in optical transceiver receivers for internal networks in AI data centers. Since multiple optical transceivers are mounted on line cards inside data center tower racks, the performance and cost efficiency of core components are critical.
ETRI's back-side lens integrated structure eliminates the need for separate light-receiving lens components, simplifying packaging and expected to reduce costs when manufacturing 800Gbps and 1.6Tbps optical modules.
Photodetector devices widely used in data centers typically offer performance of approximately 112Gbps per channel. Through this development, ETRI has enabled optical signal processing up to 224Gbps per channel, roughly doubling data processing capacity compared to existing technology.
The importance of securing ultra-high-speed, high-capacity optical device technology has grown as data traffic surges with the expansion of AI, cloud, OTT, virtual reality (VR), and augmented reality (AR) services.
The 200Gbps photodetector chip represents advanced technology that only a handful of companies worldwide can develop. ETRI succeeded in securing core foundational technology based on its indium gallium arsenide (InGaAs) photodetector technology and experience operating compound semiconductor foundries.
This achievement is expected to reduce dependence on foreign imports and strengthen the competitiveness of the domestic optical device and component industry. The single-integrated back-side lens structure is also anticipated to contribute to price competitiveness in the next-generation 800Gbps and 1.6Tbps optical module market.
"By developing core photodetector device technology applicable to the rapidly growing AI data center and 5G/6G markets for the first time in Korea, we can contribute to strengthening the competitiveness of the domestic optical component industry," said Kwon Yong-hwan, Director of ETRI's Optical Wireless Research Division.
"The key to this achievement is simultaneously securing core foundational technology and stable foundry operation capabilities in the compound optical semiconductor field, which is highly sensitive to process variables," explained Han Young-tak, Principal Researcher at ETRI's Optical Communication Components Research Lab.
ETRI has filed domestic and international patents related to this technology and completed technology transfer to Wooriro, a domestic optical component company. The institute plans to actively support industrial application and commercialization to compete with global companies in the AI data center and 5G/6G communication markets.
According to market research firm LightCounting, the global optical transceiver market is projected to grow more than threefold from $6 billion in 2019 to $18 billion in 2026.
The research results were presented at OECC 2025, the largest optical communication academic conference in the Asia-Pacific region held in Sapporo, Japan, and were recently published in the international journal Optics Express.