Pit density reduction for AlN epilayers grown by molecular beam epitaxy using Al modulation method  

作　　者：Huan Liu Peng-Fei Shao Song-Lin Chen Tao Tao Yu Yan Zi-Li Xie Bin Liu Dun-Jun Chen Hai Lu Rong Zhang Ke Wang 刘欢;邵鹏飞;陈松林;陶涛;严羽;谢自力;刘斌;陈敦军;陆海;张荣;王科(Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials,School of Electronic Science and Engineering,Nanjing University,Nanjing 210093,China;Hefei National Laboratory,Hefei 230088,China;Xiamen University,Xiamen 361005,China)

机构地区：[1]Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials,School of Electronic Science and Engineering,Nanjing University,Nanjing 210093,China [2]Hefei National Laboratory,Hefei 230088,China [3]Xiamen University,Xiamen 361005,China

出　　处：《Chinese Physics B》2024年第10期95-101,共7页中国物理B（英文版）

基　　金：supported by the Innovation Program for Quantum Science and Technology(Grant No.2021ZD0303400);the National Key R&D Program of China(Grant No.2022YFB3605602);the Key R&D Program of Jiangsu Province(Grant Nos.BE2020004-3 and BE2021026);the National Naturaal Science Foundation of China(Grant No.61974065);Jiangsu Special Professorship,Collaborative Innovation Center of Solid-State Lighting and Energysaving Electronics.

摘　　要：We have investigated homoepitaxy of AlN films grown by molecular beam epitaxy on AlN/sapphire templates byadopting both the continuous growth method and the Al modulation epitaxy(AME)growth method.The continuous growthmethod encounters significant challenges in controlling the growth mode.As the precise Al/N=1.0 ratio is difficult toachieve,either the excessive Al-rich or N-rich growth mode occurs.In contrast,by adopting the AME growth method,sucha difficulty has been effectively overcome.By manipulating the supply time of the Al and nitrogen sources,we were able toproduce AlN films with much improved surface morphology.The first step of the AME method,only supplying Al atoms,is important to wet the surface and the Al adatoms can act as a surfactant.Optimization of the initial Al supply time caneffectively reduce the pit density on the grown AlN surface.The pits density dropped from 12 pits/μm^(2)to 1 pit/μm^(2)andthe surface roughness reduced from 0.72 nm to 0.3 nm in a 2×2μm^(2)area for the AME AlN film homoepitaxially grownon an AlN template.

关 键 词：Al modulation epitaxy molecular beam epitaxy ALN PITS 

分 类 号：TB383.2[一般工业技术—材料科学与工程]