基于球差矫正电镜在原子尺度探究氮化铝在蓝宝石衬底上的生长过程  

Investigation of AlN growth on sapphire substrate at atomic scale based on spherical aberration correction electron microscope

作　　者：窦志鹏 陈召龙 李宁 刘秉尧 张敬民[2] 魏同波[4] 刘志强[4] 罗强 廖蕾 高鹏 DOU Zhi-peng;CHEN Zhao-long;LI Ning;LIU Bing-yao;ZHANG Jing-min;WEI Tong-bo;LIU Zhi-qiang;LUO Qiang;LIAO Lei;GAO Peng(Key Laboratory for Micro-/Nano-Optoelectronic Devices of Ministry of Education,School of Physics and Electronics,Hunan University,Changsha Hunan 410082;Electron Microscopy Laboratory,School of Physics,Peking University,Beijing 100871;Center for Nanochemistry (CNC),Beijing Science and Engineering Center for Nanocarbons,College of Chemistry and Molecular Engineering,Peking University,Beijing 100871;State Key Laboratory of Solid-State Lighting,Institute of Semiconductors,Chinese Academy of Sciences,Beijing 100083,Beijing Engineering Research Center for the 3rd Generation Semiconductor Materials and Application,Beijing 100083;International Center for Quantum Materials,Peking University,Beijing 100871;Collaborative Innovation Centre of Quantum Matter,Beijing 100871,China)

机构地区：[1]湖南大学物理与微电子学院微纳光电器件及应用教育部重点实验室,湖南长沙410082 [2]北京大学电子显微镜实验室,北京100871 [3]北京大学化学与分子工程学院纳米化学中心,北京100871 [4]中国科学院半导体研究所固态照明国家重点实验室,北京第三代半导体材料与应用工程研究中心,北京100083 [5]北京大学物理学院量子材料研究中心,北京100871 [6]量子物质科学协同创新中心,北京100871

出　　处：《电子显微学报》2019年第3期215-220,共6页Journal of Chinese Electron Microscopy Society

基　　金：国家重点研发资助项目(No.2018YFB0406703)

摘　　要：Ⅲ族氮化物在光电器件方面有着广泛的应用。探究Ⅲ族氮化物的外延生长机制对于制备高质量薄膜材料器件具有重要意义。本文利用球差矫正透射电子显微镜,揭示了金属有机化学气相沉积方法(MOCVD)生长的氮化铝(AlN)在蓝宝石(Al2O3)衬底上的界面原子结构,探究了异质外延的生长机制。分析发现,Al2O3衬底在氨气的氛围下退火后,表面率先被氮化,生成一层AlN。在进一步生长AlN的时候,铝(Al)原子优先填补Al2O3表面高位铝的位置,然后按照AlN的晶格结构生长。此外,该方法生长的AlN在界面附近是非金属(N)极性。这些发现加深了我们对氮化物薄膜的外延生长动力学的认识,为更好地控制界面的成核、极性提供了有用的信息。Group Ⅲ nitrides have attracted much attention due to their applications in optoelectronic devices. Here, we try to reveal the growth mechanism of AlN on sapphire substrate by revealing the atomic structure of their interface via spherical aberration correction transmission electron microscopy (Cs-TEM). We find that the sapphire surface is nitridated firstly after annealing in ammonia atmosphere to form an atomic layer of AlN and followed by filling the high-position of Al atoms on the surface. Then the growth of AlN follows the lattice structure of AlN. Furthermore,we observe that the AlN is nonmetallic (N) polarity near the interface. These findings are of great significance for understanding the growth mechanism of epitaxial growth of nitrides and also provide valuable insights into controlling the nucleation and polarity of Ⅲ nitrides.

关 键 词：球差矫正电镜 ALN 蓝宝石 界面原子结构 极性 

分 类 号：TG115.215.3[金属学及工艺—物理冶金] TN304[金属学及工艺—金属学]