Surface diffusion effects on growth of nanowires by chemical beam epitaxy
Surface diffusion effects on growth of nanowires by chemical beam epitaxy
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DOI：
10.1063/1.2435800
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发表时间：
2007-02-01
影响因子：
3.2
通讯作者：
Samuelson, L.
中科院分区：
文献类型：
--
作者：
Persson, A. I.;Froberg, L. E.;Samuelson, L.
表面过程在化学束外延生长半导体纳米线中起着重要的作用。特别是，对于III-V纳米线，为了控制纳米线的生长，了解III族物种的表面扩散是重要的。本文采用电子束曝光法生长了InAs基纳米线，通过测量不同纳米线间距下的纳米线生长速率，研究了In物种的扩散随温度、-III族和-V族源压力以及-V族源组合的变化规律。我们提出了一个模型，将纳米线的生长速度与In物种的迁移长度联系起来。以迁移长度作为拟合参数，对不同生长条件下的实验数据进行了拟合。结果表明，迁移长度随温度的降低和V/III源压比的增大而增大。这通常会导致生长速度的增加，但由于不完全分解和第三类物种粘连系数的变化，会出现偏差。结果还表明，引入磷前驱体生长InAs1-xPx纳米线，减小了In物种的迁移长度，从而降低了纳米线的生长速度。(C)2007年美国物理研究所。
Surface processes play a large role in the growth of semiconductor nanowires by chemical beam epitaxy. In particular, for III-V nanowires the surface diffusion of group-III species is important to understand in order to control the nanowire growth. In this paper, we have grown InAs-based nanowires positioned by electron beam lithography and have investigated the dependence of the diffusion of In species on temperature, group-III and -V source pressure and group-V source combinations by measuring nanowire growth rate for different nanowire spacings. We present a model which relates the nanowire growth rate to the migration length of In species. The model is fitted to the experimental data for different growth conditions, using the migration length as fitting parameter. The results show that the migration length increases with decreasing temperature and increasing group-V/group-III source pressure ratio. This will most often lead to an increase in growth rate, but deviations will occur due to incomplete decomposition and changes in sticking coefficient for group-III species. The results also show that the introduction of phosphorous precursor for growth of InAs1-xPx nanowires decreases the migration length of the In species followed by a decrease in nanowire growth rate. (c) 2007 American Institute of Physics.