High-Density, Defect-Free, and Taper-Restrained Epitaxial GaAs Nanowires Induced from Annealed Au Thin Films
High-Density, Defect-Free, and Taper-Restrained Epitaxial GaAs Nanowires Induced from Annealed Au Thin Films
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DOI：
10.1021/cg201725g
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发表时间：
2012-03
影响因子：
3.8
通讯作者：
Hong-yi Xu;Yong Wang;Yanan Guo;Z. Liao;Q. Gao;N. Jiang;H. Tan;C. Jagadish;J. Zou
中科院分区：
文献类型：
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作者：
Hong-yi Xu;Yong Wang;Yanan Guo;Z. Liao;Q. Gao;N. Jiang;H. Tan;C. Jagadish;J. Zou
在这项研究中，我们证明了使用退火金薄膜作为催化剂，在GaAs(111)B衬底上生长了高密度、无缺陷和锥形约束的外延GaAs纳米线。在相同的金属-有机化学气相沉积反应器中，比较了在相同条件下生长的纳米线和低密度Au胶体纳米粒子催化生长的GaAs纳米线。通过用先进的电子显微镜进行详细的形貌和结构表征，我们发现增加Au催化剂的密度可以有效地抑制GaAs外延纳米线的锥化。通过增加Au催化剂的密度，降低了纳米线的轴向生长速度，从而限制了晶格缺陷的形成。此外，对不同厚度的Au薄膜(1 nm、2 nm、3 nm和5 nm)和不同密度的Au胶体粒子催化的GaAs纳米线的综合研究表明，Au催化剂的密度对GaAs纳米线的生长起着重要的作用。这一全面的研究为探索III-V外延半导体纳米线的催化剂效应和生长机理提供了机会。
In this study, we demonstrated that by using annealed Au thin films as catalysts, high-density, defect-free, and taper-restrained epitaxial GaAs nanowires were grown on GaAs (111)B substrates. The as-grown nanowires were compared with low-density Au colloidal nanoparticle catalyzed GaAs nanowires grown under identical conditions in the same metal–organic chemical vapor deposition reactor. Through detailed morphological and structural characterizations using advanced electron microscopy, we discovered that GaAs epitaxial nanowire tapering can be efficiently restrained by increasing the density of Au catalysts. By increasing the density of the Au catalysts, the axial growth rate of nanowires is reduced, which, in turn, limits the formation of lattice defects. Furthermore, the comprehensive investigation of GaAs nanowires catalyzed by Au thin film of different thicknesses (1 nm, 2 nm, 3 nm, and 5 nm) and Au colloidal particles of different densities indicates that the density of the Au catalysts play an important role in GaAs nanowire growth. This comprehensive study provides an opportunity to explore the effects of the catalysts and the growth mechanisms of III–V epitaxial semiconductor nanowires.