Increased bismuth concentration in MBE GaAs1−xBix films by oscillating III/V flux ratio during growth
Increased bismuth concentration in MBE GaAs1−xBix films by oscillating III/V flux ratio during growth
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通过在生长过程中振荡 III/V 通量比增加 MBE GaAs1−xBix 薄膜中的铋浓度
DOI：
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发表时间：
2015
期刊：
影响因子：
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通讯作者：
A. Brown
中科院分区：
文献类型：
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作者：
A. Wood;S. Babcock;Jincheng Li;A. Brown
用高角度环状暗场成像(Z-衬度成像)，结合X射线衍射，研究了分子束外延生长的GaAs_1-−_xBix薄膜中铋的浓度分布。样品在每个成分助熔剂中都有梯度生长，因此，基材上的III/V比率也是如此。在生长过程中旋转样品使生长表面暴露在振荡的III/V通量比下。正弦[Bi]分布导致了生长方向，其波长和数目与生长速率和衬底旋转速率一致。然而，在观察到的波动中，[Bi]的大小大于在固定衬底上使用相同的Bi通量和Ga/As通量比在稳态条件下获得的最大[Bi值]，这表明在生长过程中改变III/V通量比促进了Bi在GaAs1−xBix薄膜中的掺入。提出了一种定性的模型，用于解释如何实现这一目标。
The authors have examined bismuth concentration profiles in GaAs1−xBix films grown by molecular beam epitaxy using high angle annular dark field imaging (Z-contrast imaging) in an aberration-corrected scanning transmission electron microscope in conjunction with x-ray diffraction. Samples were grown with a gradient in each of the component fluxes, and therefore, the III/V ratio across the substrate. Rotating the sample during growth exposed the growth surface to an oscillating III/V flux ratio. Sinusoidal [Bi] profiles resulted in the growth direction, the wavelength and number of which were consistent with the growth rate and the rate of substrate rotation. However, the magnitude of [Bi] in the observed fluctuations was greater than the maximum [Bi] achieved using the same Bi flux and Ga/As flux ratios in steady-state conditions on a stationary substrate, suggesting that varying the III/V flux ratio during growth promotes the incorporation of Bi in GaAs1−xBix films. A proposed qualitative model for how t...
影响因子：
1.8
作者：
P. Ludewig;Nikolai Knaub;W. Stolz;K. Volz
通讯作者：
P. Ludewig;Nikolai Knaub;W. Stolz;K. Volz