Yeu, In Won Han, Gyuseung Park, Jaehong Hwang, Cheol Seong Choi, Jung-Hae 2024-01-19T18:32:24Z 2024-01-19T18:32:24Z 2022-01-11 2019-12-15 0169-4332 https://pubs.kist.re.kr/handle/201004/119190 The catalyst-free growth of the GaAs nanowire is based on preferential one-dimensional growth along the < 111 > B direction of the zinc-blende-structure GaAs, which originates from the formation of facets depending on the temperature and pressure. However, the driving force for preferential growth has yet to be fully elucidated. In this study, the adsorption-desorption behavior for several low-index surfaces was investigated in terms of temperature, pressure, and surface reconstruction using ab-initio thermodynamics. It was found that the As adsorption on the (111)B surface is highly favorable compared to that on the other surfaces under the experimental conditions, where the growth of the GaAs nanowires was successful without catalyst. Based on the thorough calculations and a comparison of the results with those of previous experiments, the driving force behind the preferential one-dimensional growth along the < 111 > B direction is confirmed to be the preferential adsorption of As on the (111) B surface under the specific temperature and pressure condition. In particular, the Ga-vacancy alpha(2x2) reconstruction of the (111)B surface, which was calculated to be stable at high temperature, is identified to provide the preferential adsorption sites for the incoming vapor sources. English ELSEVIER INITIO MOLECULAR-DYNAMICS TOTAL-ENERGY CALCULATIONS STRUCTURAL STABILITY TEMPERATURE SIMULATION DEPENDENCE PRESSURE SILICON Theoretical understanding of the catalyst-free growth mechanism of GaAs < 111 > B nanowires Article 10.1016/j.apsusc.2019.143740 1 APPLIED SURFACE SCIENCE, v.497 APPLIED SURFACE SCIENCE 497 scie scopus 000487849800033 2-s2.0-85071670941 Chemistry, Physical Materials Science, Coatings & Films Physics, Applied Physics, Condensed Matter Chemistry Materials Science Physics Article INITIO MOLECULAR-DYNAMICS TOTAL-ENERGY CALCULATIONS STRUCTURAL STABILITY TEMPERATURE SIMULATION DEPENDENCE PRESSURE SILICON GaAs nanowire (111)B reconstruction Surface vibration Adsorption Ab-initio thermodynamics