高速光探测器的集成微透镜结构设计与制备  

Design and Fabrication of Integrated Microlens for High Speed Photodetectors

作　　者：杨晓伟[1] 袁纬方 李同辉 李玉[1] 董晓雯 刘凯[1] 黄永清[1] 段晓峰[1] YANG Xiaowei;YUAN Weifang;LI Tonghui;LI Yu;DONG Xiaowen;LIU Kai;HUANG Yongqing;DUAN Xiaofeng(State Key Laboratory of Information Photonics and Optical Communications,Beijing University of Posts and Telecommunications,Beijing 100876,China)

机构地区：[1]北京邮电大学信息光子学与光通信国家重点实验室,北京100876

出　　处：《光子学报》2023年第8期109-118,共10页Acta Photonica Sinica

基　　金：创新研究群体项目(No.62021005);国家重点研发计划(No.2018YFB2200803)。

摘　　要：高速光探测器以获得更高的3 dB带宽为目标,减小器件台面面积能够使结电容降低从而提高带宽,但同时也增大了系统中的光耦合损耗。针对该问题,在高速光探测器衬底背面单片集成微透镜结构是一种有效的解决方案,该结构可通过补偿对准偏差来提高器件的光耦合效率。设计了一种面向数据中心应用的,与1.31μm光探测器芯片单片集成的InP基微透镜结构;通过热熔法制作微透镜胶型,并利用电感耦合等离子体刻蚀实现微透镜胶型转移,电感耦合等离子体刻蚀过程选择SiCl4和Ar作为刻蚀气体以保证实验的安全性;制备了一种直径90.3μm、冠高18.5μm、表面形貌光滑的InP基微透镜结构。单片集成微透镜的PIN光探测器在1.31μm波长处,入射光偏离主光轴3°的情况下,光探测器的响应度仅下降4%。With the accelerated development of new industries such as big data and cloud computing,higher requirements are put forward for the capacity of communication networks.Due to the limitations of electrical interconnection,optical interconnection occupies an increasing proportion in the communication system.In order to meet the demand of rapid increase of optical communication network capacity,improving the transmission rate of single channel is an effective solution.Therefore,high speed optical detector is widely used in optical communication system.The goal of high speed optical detector is to obtain a higher bandwidth of 3 dB,and reducing the surface area of the device is an effective way to achieve it.The decrease of the mesa area can reduce the junction capacitance of the optical detector and thus improve the bandwidth of the optical detector.However,the decrease of the mesa area can reduce the optical coupling efficiency of the optical detector and directly increase the optical coupling loss in the system.To solve this problem,the monolithic integrated microlens structure on the back of high speed optical detector substrate is an effective solution.The structure increases the equivalent photosensitive surface of the optical detector,increases the optical coupling efficiency of the optical detector,and can effectively compensate the alignment deviation.An InP-based microlens structure integrated with a 1.31 μm optical detector chip is designed for data center applications.An InP-based microlens structure integrated with a 1.31 μm optical detector chip is designed for data center applications.An experimental method was developed to fabricate microlens glue by hot melt and transfer microlens glue by Inductively Coupled Plasma(ICP) etching.SiCl4and Ar were selected as etching gases in ICP etching process to ensure the safety of the experiment.An InP-based microlens with diameter of 90.3 μm,crown height of 18.5 μm and smooth surface morphology was prepared.In this paper,a single InP microlens integrated on the

关 键 词：集成微透镜 光探测器 微透镜胶型 热熔法 电感耦合等离子体刻蚀 

分 类 号：TN364.2[电子电信—物理电子学]