Co-packaged optics (CPO): status, challenges, and solutions

Min Tan; Jiang Xu; Siyang Liu; Junbo Feng; Hua Zhang; Chaonan Yao; Shixi Chen; Hangyu Guo; Gengshi Han; Zhanhao Wen; Bao Chen; Yu He; Xuqiang Zheng; Da Ming; Yaowen Tu; Qiang Fu; Nan Qi; Dan Li; Li Geng; Song Wen; Fenghe Yang; Huimin He; Fengman Liu; Haiyun Xue; Yuhang Wang; Ciyuan Qiu; Guangcan Mi; Yanbo Li; Tianhai Chang; Mingche Lai; Luo Zhang; Qinfen Hao; Mengyuan Qin

doi:10.1007/s12200-022-00055-y

Co-packaged optics (CPO): status, challenges, and solutions

Front Optoelectron. 2023 Mar 20;16(1):1. doi: 10.1007/s12200-022-00055-y.

Authors

Min Tan^#^{1

2}, Jiang Xu^{3

4

5}, Siyang Liu^#⁶, Junbo Feng⁷, Hua Zhang^#⁸, Chaonan Yao⁹, Shixi Chen^#¹⁰, Hangyu Guo^#¹¹, Gengshi Han^#¹¹, Zhanhao Wen^#¹¹, Bao Chen^#¹¹, Yu He^#¹¹, Xuqiang Zheng^#¹², Da Ming^#¹³, Yaowen Tu¹³, Qiang Fu^#¹³, Nan Qi¹⁴, Dan Li^#¹⁵, Li Geng¹⁶, Song Wen^#¹¹, Fenghe Yang¹⁷, Huimin He¹¹, Fengman Liu¹¹, Haiyun Xue^#¹⁸, Yuhang Wang¹³, Ciyuan Qiu¹⁹, Guangcan Mi^#²⁰, Yanbo Li²⁰, Tianhai Chang²¹, Mingche Lai^#²², Luo Zhang²³, Qinfen Hao²⁴, Mengyuan Qin²⁵

Affiliations

¹ School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, China. mtan@hust.edu.cn.
² Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, China. mtan@hust.edu.cn.
³ Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology, Hong Kong, China. jiang.xu@ust.hk.
⁴ HKUST Fok Ying Tung Research Institute, Guangzhou, 511462, China. jiang.xu@ust.hk.
⁵ The Hong Kong University of Science and Technology (Guangzhou), Guangzhou, 511462, China. jiang.xu@ust.hk.
⁶ Chongqing United Micro-Electronics Center (CUMEC), Chongqing, 401332, China.
⁷ Chongqing United Micro-Electronics Center (CUMEC), Chongqing, 401332, China. junbo.feng@cumec.cn.
⁸ Hisense Broadband Multimedia Technologies Co., Ltd., Qingdao, 266000, China. zhanghua8@hisense.com.
⁹ Hisense Broadband Multimedia Technologies Co., Ltd., Qingdao, 266000, China.
¹⁰ Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology, Hong Kong, China.
¹¹ Institute of Microelectronics, Chinese Academy of Sciences, Beijing, 100029, China.
¹² Institute of Microelectronics, Chinese Academy of Sciences, Beijing, 100029, China. zhengxuqiang@ime.ac.cn.
¹³ School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, China.
¹⁴ State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China.
¹⁵ School of Microelectronics, Xi'an Jiaotong University, Xi'an, 710049, China. dan.li@xjtu.edu.cn.
¹⁶ School of Microelectronics, Xi'an Jiaotong University, Xi'an, 710049, China.
¹⁷ Zhangjiang Laboratory, Shanghai, 201210, China.
¹⁸ Institute of Microelectronics, Chinese Academy of Sciences, Beijing, 100029, China. xuehaiyun@ime.ac.cn.
¹⁹ The State Key Laboratory of Advanced Optical Communication Systems and Networks, Department of Electronic Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China. qiuciyuan@sjtu.edu.cn.
²⁰ Huawei Technologies Co., Ltd., Shenzhen, 440307, China.
²¹ Huawei Technologies Co., Ltd., Shenzhen, 440307, China. changtianhai@huawei.com.
²² College of Computer, National University of Defense Technology, Changsha, 410073, China.
²³ College of Computer, National University of Defense Technology, Changsha, 410073, China. jiiftluo@nudt.edu.cn.
²⁴ Institute of Computing Technology, Chinese Academy of Sciences, Beijing, 100086, China. haoqinfen@ict.ac.cn.
²⁵ Institute of Computing Technology, Chinese Academy of Sciences, Beijing, 100086, China.

^# Contributed equally.

Abstract

Due to the rise of 5G, IoT, AI, and high-performance computing applications, datacenter traffic has grown at a compound annual growth rate of nearly 30%. Furthermore, nearly three-fourths of the datacenter traffic resides within datacenters. The conventional pluggable optics increases at a much slower rate than that of datacenter traffic. The gap between application requirements and the capability of conventional pluggable optics keeps increasing, a trend that is unsustainable. Co-packaged optics (CPO) is a disruptive approach to increasing the interconnecting bandwidth density and energy efficiency by dramatically shortening the electrical link length through advanced packaging and co-optimization of electronics and photonics. CPO is widely regarded as a promising solution for future datacenter interconnections, and silicon platform is the most promising platform for large-scale integration. Leading international companies (e.g., Intel, Broadcom and IBM) have heavily investigated in CPO technology, an inter-disciplinary research field that involves photonic devices, integrated circuits design, packaging, photonic device modeling, electronic-photonic co-simulation, applications, and standardization. This review aims to provide the readers a comprehensive overview of the state-of-the-art progress of CPO in silicon platform, identify the key challenges, and point out the potential solutions, hoping to encourage collaboration between different research fields to accelerate the development of CPO technology.

Keywords: Advanced packaging; Co-packaged optics; Co-simulation; External laser; High-performance computing; Optical power delivery; Receiver; Silicon photonics; Standardization; Transmitter.