title: Growth of InAs Quantum Dots on GaAs (511)A Substrates: The Competition between Thermal Dynamics and Kinetics.
abstract: The growth process of InAs quantum dots grown on GaAs (511)A substrates has been studied by atomic force microscopy. According to the atomic force microscopy studies for quantum dots grown with varying InAs coverage, a noncoherent nucleation of quantum dots is observed. Moreover, due to the long migration length of In atoms, the Ostwald ripening process is aggravated, resulting in the bad uniformity of InAs quantum dots on GaAs (511)A. In order to improve the uniformity of nucleation, the growth rate is increased. By studying the effects of increased growth rates on the growth of InAs quantum dots, it is found that the uniformity of InAs quantum dots is greatly improved as the growth rates increase to 0.14 ML s(-1) . However, as the growth rates increase further, the uniformity of InAs quantum dots becomes dual-mode, which can be attributed to the competition between Ostwald ripening and strain relaxation processes. The results in this work provide insights regarding the competition between thermal dynamical barriers and the growth kinetics in the growth of InAs quantum dots, and give guidance to improve the size uniformity of InAs quantum dots on (N11)A substrates.
authors.affiliation: State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou, 510641, P. R. China.|Engineering Research Center on Solid-State Lighting and its Informationisation of Guangdong Province, South China University of Technology, Guangzhou, 510641, P. R. China.|Department of Electronic Materials, School of Materials Science and Engineering, South China University of Technology, Guangzhou, 510640, P. R. China.
authors.forename: Lei
authors.initials: L
authors.lastname: Wen
authors.affiliation: State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou, 510641, P. R. China.|Engineering Research Center on Solid-State Lighting and its Informationisation of Guangdong Province, South China University of Technology, Guangzhou, 510641, P. R. China.|Department of Electronic Materials, School of Materials Science and Engineering, South China University of Technology, Guangzhou, 510640, P. R. China.
authors.forename: Fangliang
authors.initials: F
authors.lastname: Gao
authors.affiliation: State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou, 510641, P. R. China.|Engineering Research Center on Solid-State Lighting and its Informationisation of Guangdong Province, South China University of Technology, Guangzhou, 510641, P. R. China.|Department of Electronic Materials, School of Materials Science and Engineering, South China University of Technology, Guangzhou, 510640, P. R. China.
authors.forename: Shuguang
authors.initials: S
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou, 510641, P. R. China.|Engineering Research Center on Solid-State Lighting and its Informationisation of Guangdong Province, South China University of Technology, Guangzhou, 510641, P. R. China.|Department of Electronic Materials, School of Materials Science and Engineering, South China University of Technology, Guangzhou, 510640, P. R. China.
authors.forename: Guoqiang
authors.initials: G
authors.lastname: Li
keywords: GaAs (511)A; Ostwald ripening; molecular beam epitaxy; quantum dots; surface fluctuations