利用InAs/GaAs数字合金超晶格改进InAs量子点有源区的结构设计  

Improving structure design of active region of InAs quantum dots by using InAs/GaAs digital alloy superlattice

作　　者：杜安天 刘若涛 曹春芳[2] 韩实现 王海龙 龚谦[2,3] Du An-Tian;Liu Ruo-Tao;Cao Chun-Fang;Han Shi-Xian;Wang Hai-Long;Gong Qian(Shandong Provincial Key Laboratory of Laser Polarization and Information Technology,School of Physics and Physical Engineering,Qufu Normal University,Qufu 273165,China;Key Laboratory of Terahertz Solid State Technology,Shanghai Institute of Microsystem and Information Technology,Chinese Academy of Sciences,Shanghai 200050,China;Center of Materials Science and Optoelectronics Engineering,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]曲阜师范大学物理工程学院,山东省激光偏光与信息技术重点实验室,曲阜273165 [2]中国科学院上海微系统与信息技术研究所,中科院太赫兹固态技术重点实验室,上海200050 [3]中国科学院大学材料科学与光电子工程中心,北京100049

出　　处：《物理学报》2023年第12期279-285,共7页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:61674096)资助的课题。

摘　　要：利用分子束外延技术,通过InAs/GaAs数字合金超晶格代替传统的直接生长InGaAs层的方式,在GaAs(100)衬底上生长了InAs量子点结构并成功制备了1.3μm InAs量子点激光器.通过原子力显微镜和光致荧光谱测试手段,对传统生长模式和数字合金超晶格生长模式的两种样品进行了表征,研究发现采用32周期InAs/GaAs数字合金超晶格样品的量子点密度非常高,发光性能良好.通过与常规生长方式所制备激光器的性能对比,发现采用InAs/GaAs数字合金超晶格生长InAs量子点的有源区也可以得到高质量的激光器.利用该方式生长的InAs量子点激光器的阈值电流为24 mA,相应的阈值电流密度仅为75 A/cm^(2),最高工作温度达到120℃.InAs/GaAs数字合金超晶格既可以保证生长过程中源炉的温度保持不变,还可以对InGaAs层的组分实现灵活调控.不需要改变生长速度,通过改变InAs/GaAs数字合金超晶格的周期数以及InAs层和GaAs层的厚度,便可以获得任意组分的InGaAs,从而得到不同发光波长的激光器.这种生长方式对量子点有源区的结构设计和外延生长提供了新思路.A 1.3-μm InAs quantum dot laser has been successfully fabricated on a GaAs(100)substrate by molecular beam epitaxy(MBE)technique through using InAs/GaAs digital alloy superlattices instead of the conventional InGaAs layer.The samples grown by conventional growth method and the digital alloy superlattice growth method are characterized by atomic force microscope(AFM)and photoluminescence(PL)spectroscopy.It is found that 8-period sample possesses a low quantum dot density and poor luminescence performance.With the increase of the number of growth periods,the quantum dot density of the sample increases and the luminous performance improves.This indicates that the quality of the grown sample improves with the increase of InAs/GaAs period of the InGaAs layer.When the total InAs/GaAs period is 32,the quantum dot density of the sample is high and the luminescence performance is good.After the experimental measurement,the sample DAL-0 fabricated by conventional growth method and the sample DAL-32(32-periods InAs/GaAs digital alloy superlattices)are utilized to fabricate quantum dot laser by standard process.The performances of two types of quantum dot lasers obtained with different growth methods are characterized.It is found that the InAs quantum dot lasers fabricated by the sample grown by digital alloy superlattice method have good performances.Under continuous wave operation mode,the threshold current is 24 mA corresponding to a threshold current density of 75 A/cm2.The highest operation-temperature reaches 120℃.In addition,InAs quantum dot laser using digital alloy superlattice has good temperature stability.Its characteristic temperature is 55.4 K.Compared with the traditional laser,the InAs quantum dot laser grown by InAs/GaAs digital alloy superlattice has good performance in terms of threshold current density,output power and temperature stability,which indicates that high-quality laser can be obtained by this growth method.Using the InAs/GaAs digital alloy superlattice growth method,the InGaAs composition ca

关 键 词：量子点 半导体激光器 分子束外延 数字合金超晶格 

分 类 号：TN248.4[电子电信—物理电子学] O413[理学—理论物理]