Kim, HS Suh, JH Park, CG Lee, SJ Noh, SK Song, JD Park, YJ Choi, WJ Lee, JI 2024-01-21T04:06:26Z 2024-01-21T04:06:26Z 2021-09-02 2005-11-15 0022-0248 https://pubs.kist.re.kr/handle/201004/135983 The structure and thermal stability of self-assembled InAs/GaAs quantum dots (QDs) grown by atomic layer epitaxy (ALE) and molecular beam epitaxy (MBE) QDs were studied using high-resolution electron microscopy with in situ heating experiment capabilities. The ALE QDs were larger and more regular shaped than MBE QDs because of the higher diffusivity of In compared with that of InAs in MBE growth. The QDs were found to form a lens-shaped structure with side facets in the early stage of growth. Upon capping with a GaAs layer, however, the QD apexes flattened because of the diffusion of In and As from the QDs. The structural behavior of QDs at elevated temperatures was observed directly on the atomic scale by in situ heating experiments within TEM. The in situ high-resolution electron microscopy revealed that the uncapped ALE and MBE QDs remained stable up to 580 degrees C. However, above 600 degrees C, the QDs collapsed due to the diffusion and evaporation of In and As from the QDs. (c) 2005 Elsevier B.V. All rights reserved. English ELSEVIER RADIATION-DAMAGE STRAIN SURFACE TEM Structure and thermal stability of InAs/GaAs quantum dots grown by atomic layer epitaxy and molecular beam epitaxy Article 10.1016/j.jcrysgro.2005.08.020 1 JOURNAL OF CRYSTAL GROWTH, v.285, no.1-2, pp.137 - 145 JOURNAL OF CRYSTAL GROWTH 285 1-2 137 145 scie scopus 000233152500020 2-s2.0-27144538842 Crystallography Materials Science, Multidisciplinary Physics, Applied Crystallography Materials Science Physics Article RADIATION-DAMAGE STRAIN SURFACE TEM thermal stability of quantum dot transmission electron microscopy (TEM) quantum dot structure InAs/GaAs quantum dot