Co-packaged optics (CPO) means that optical and electronic devices are put in the same tiny package and work together. In traditional switches, the optical module is farther away from the switch chip, the signal transmission distance is long, and the transmission time is longer, thus causing delay problems. In addition, long interconnect distances also consume more power. The co-packaged optics significantly shortens the interconnect distance, greatly reduces the delay and power consumption, and is regarded as one of the development directions of future data center optical interconnect technology. At present, many companies, including Intel, Cisco, Marvell, and Broadcom, are optimistic about the application prospects of this technology and actively promote the development of CPO technology. However, the high integration density of CPO technology brings a series of new challenges.
Researchers led by Prof. Haiyun Xue at the Institute of Microelectronics of the Chinese Academy of Sciences (IMECAS) are dedicated to solving the various challenges faced by CPO. Thermal management difficulty is one of the challenges limiting CPO development. In this paper, a series of research studies have been conducted on the thermal management of the CPO, and a corresponding thermal management scheme has been designed according to the layout and heat dissipation requirements of the CPO. The scheme can efficiently cool the high heat flux switch chip and avoid the high temperature generated by the switch chip from affecting the surrounding optical modules. And it can also ensure the temperature homogeneity between the surrounding optical modules to avoid signal crosstalk. This solution can well meet the heat dissipation demands of CPOs, and through simulation and experimental verification, it can be applied to the heat dissipation of 51.2 Tbit/s CPOs. This technology can effectively solve the thermal management difficulties of CPO and release the performance potential of CPO technology. The work entitled “Simulation and Experimental Investigation of Liquid-Cooling Thermal Management for High-Bandwidth Co-Packaged Optics” was published on Frontiers of Optoelectronics (published on May 14, 2025).
DOI: 10.1007/s12200-025-00156-4