对称负极芯片结构改善硅基激光器性能研究  

Improved Performances of Lasers on Silicon(001)with Symmetrical Cathode Structures

作　　者：马博杰 王俊[1] 刘昊[1] 江晨 刘倬良 翟浩 李健[2] 明蕊 葛庆 林枫[1] 刘凯[1] 王琦[1] 韦欣[2] 黄永清[1] 任晓敏[1] Ma Bojie;Wang Jun;Liu Hao;Jiang Chen;Liu Zhuoliang;Zhai Hao;Li Jian;Ming Rui;Ge Qing;Lin Feng;Liu Kai;Wang Qi;Wei Xin;Huang Yongqing;Ren Xiaomin(State Key Laboratory of Information Photonics and Optical Communications,Beijing University of Posts and Telecommunications,Beijing 100876,China;Institute of Semiconductors,Chinese Academy of Sciences,Beijing 100083,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 [2]中国科学院半导体研究所,北京100083

出　　处：《中国激光》2023年第11期235-241,共7页Chinese Journal of Lasers

基　　金：国家自然科学基金(61874148);国家重点研发计划重点专项课题(2018YFB2200104);北京市科技计划课题(Z191100004819012);国家创新研究群体科学基金(62021005);信息光子学与光通信国家重点实验室(北京邮电大学)基金(IPOC2022ZZ01);高校学科创新引智计划(BP0719012);北京邮电大学研究生创新创业项目(2022-YC-T031)。

摘　　要：本课题组设计了一种用于硅基外延激光器的对称负极芯片结构,与传统共面电极芯片结构相比,该结构大幅降低了硅基激光器的微分电阻,使激光器性能显著提升。采用该电极结构以及基于无偏角Si(001)衬底的量子点激光器外延材料进行了激光器芯片制作。芯片尺寸为1500μm×50μm的激光器的微分电阻仅为1.52Ω,单面输出光功率可达70 mW。实验结果表明:相比于传统共面电极芯片结构,该芯片结构可将器件的微分电阻降低约75%;当注入电流从1.2倍阈值电流增大到2.8倍阈值电流时,激射波长红移量减少了约77%,特征温度由27.2 K提高到43.4 K,斜率效率增大了约26.4%,最大光电转换效率增大了约4.7倍。所设计的芯片结构方案为制作高性能硅基外延激光器提供了一种优化的技术途径。Objective Investigations of silicon-based optoelectrical integration have become a development trend for an increased transmission rate in optical networks.Currently,most photonic devices achieve on-chip integration,except for silicon-based lasers,which are essential light sources.Heterogeneous epitaxial growth has been used to construct silicon-basedⅢ-Ⅴsemiconductor laser structures,and it is one of the most promising solutions offering high yield and low costs.Significant efforts have been made to enhance the performance of silicon-based lasers by improving the quality of the as-grown material.However,only a few studies have been conducted on optimizing the laser-chip structure and the fabrication process that directly influences the lasing modes,differential resistances,and other properties of the lasers.Moreover,high differential resistance can reduce the output power,slope efficiency,and wall-plug efficiency(WPE)of the lasers and can even cause lasing failure owing to excessive waste heat.Therefore,reducing the differential resistance of silicon-based lasers is critical for significantly improving laser performance and realizing high-performance silicon-based lasers.Methods Combined with the advantages of metalorganic chemical vapor deposition(MOCVD)and molecular beam epitaxy(MBE),the quantum-dot(QD)laser structure was grown on a two-inch complementary metal-oxide semiconductor(CMOS)-compatible Si(001)substrate(Fig.1).Moreover,Fabry-Perot(F-P)laser devices were fabricated using two different chip structures.The ridges were etched using inductively coupled plasma(ICP)via standard photolithography.Ti/Pt/Au and AuGe/Ni/Au were deposited via physical vapor deposition(PVD)as p-and n-type contact electrodes,respectively.A 300 nm thick SiO2 layer was deposited via plasma-enhanced chemical vapor deposition(PECVD)for electrical isolation.The as-fabricated wafers were fabricated into different chip sizes by adequate cleaving and then mounted on Cu heatsinks with C-mount packages.Finally,the main performance of the

关 键 词：激光器 硅基激光器 直接外延 对称负极结构 微分电阻 

分 类 号：TN365[电子电信—物理电子学]