Al_(0.17)Ga_(0.83)As/GaAs(001)薄膜退火过程的热力学分析  

Thermodynamic analysis of Al_(0.17)Ga_(0.83)As/GaAs(001) in annealing process

作　　者：王一[1,2] 杨晨 郭祥[1,2] 王继红[1,2] 刘雪飞[1,3] 魏节敏 郎啟智[1,3] 罗子江 丁召 Wang Yi;Yang Chen;Guo Xiang;Wang Ji-Hong;Liu Xue-Fei;Wei Jie-Ming;Lung Qi-Zhi;Luo Zi-Jiang;Ding Zhao(College of Big Data and Information Engineering, Guizhou University, Guiyang 550025, China;School of Education Administrations, Guizhou University of Finance and Economics, Guiyang 550025, China;Power Semiconductor Device Reliability Center of the Ministry of Education, Guiyang 550025, China;Key Laboratory of Micro-Nano-E1ectronics of Guizhou Province, Guiyang 550025, China)

机构地区：[1]贵州大学大数据与信息工程院,贵阳550025 [2]教育部半导体功率器件可靠性工程中心,贵阳550025 [3]贵州省微纳电子与软件技术重点实验室,贵阳550025 [4]贵州财经大学教育管理学院,贵阳550025

出　　处：《物理学报》2018年第8期33-38,共6页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:61564002;11664005;61604046);贵州省科学技术基金(批准号:黔科合J字[2014]2046;黔科合LH字[2016]7436;黔科合基础[2017]1055)资助的课题~~

摘　　要：在As_4束流等效压强为1.2×10^(-3)Pa、退火60 min条件下改变退火温度,对Al_(0.17)Ga_(0.83)As/GaAs薄膜表面平坦化的条件进行了探讨.定量分析了薄膜表面坑、岛与平台的覆盖率和台阶-平台间薄膜粗糙度随退火温度变化的规律,得到最合适的退火温度为545℃(±1℃);根据退火模型发现退火温度的改变会影响参与熟化的原子的数量,熟化原子比θ正比于退火温度,即θ∝Τ.退火温度540℃条件下退火约60 min,薄膜表面达到基本平坦,推测此时0.20<θ<0.25;退火温度为545℃时,推测退火时间约为55-60 min.本实验得到的结论可以为生长平坦的Al_(0.17)Ga_(0.83)As/GaAs薄膜提供理论与实验指导.For matching lattice parameters, AlGaAs alloy is usually grown on a GaAs（001） substrate. The AlGaAs/GaAs multilayer structure has been widely used to manufacture various photoelectric and electronic devices. The practical importance of atomic flat surfaces lies in improving the performances of modern optoelectronic devices based on AlGaAs/GaAs multilayer structure. The influence of temperature on the flatness of the film has not been analyzed in detail, so it is very important to prepare the surface at an atomic level by adjusting annealing temperature. In this paper, 15 ML Al_（0.17）Ga_（0.83）As are deposited on an n-doped GaAs（001） substrate by the molecular beam epitaxy（MBE） technique. We study the effects of various annealing temperatures（520 ℃, 530 ℃, 540 ℃） on the flattening of Al_（0.17）Ga_（0.83）As/GaAs（001） surface under the same condition of arsenic BEP about 1.2×10^（-3） Pa, annealing time60 min and growth rate（0.17 ML/s）. The（1000 nm×1000 nm） scanning tunneling microscope（STM） images and Fourier transform graphs are obtained to show the evolution of surface morphology. In a temperature range of 520-530℃, island is ripening, the coverage of the island increases, the pit also begins to merge into a larger pit; when the temperature exceeds 530 ℃, the increasing of ripening rate leads to a big island and the pit turns into terrace,while the coverage of island and the pit gradually decreases. In the annealing process, the area of terrace increases and gradually approaches to 100%. By quantitatively analysing the coverage of pit（island, terrace） and root mean square（RMS） roughness varying with the annealing temperature, a 545 ℃（±1℃） better annealing temperature is proposed by fitting the curve of RMS roughness variation. At the same time, the film annealing model is analyzed in this paper.Comparing the results in the literature with our experimental data, it is found that the change of annealing temperature can influence the number

关 键 词：ALGAAS 薄膜 退火 

分 类 号：O484[理学—固体物理]