Formation and characterization of high-density FeSi nanodots on SiO2 induced by remote H2 plasma
Formation and characterization of high-density FeSi nanodots on SiO2 induced by remote H2 plasma
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DOI：
10.7567/jjap.55.01ae20
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发表时间：
2015
影响因子：
1.5
通讯作者：
Hai Zhang;K. Makihara;A. Ohta;M. Ikeda;S. Miyazaki
中科院分区：
文献类型：
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作者：
Hai Zhang;K. Makihara;A. Ohta;M. Ikeda;S. Miyazaki
我们通过将电子束蒸发的 Fe/非晶硅/铁 (Fe/a-Si/Fe) 三层堆叠暴露于远程 H2 等离子体而无需任何外部加热，演示了在热生长 SiO2 上形成高密度硅化铁纳米点 (ND)，并表征了它们的硅化状态和晶相。远程 H2 等离子体暴露后，证实形成了面密度为 ∼4.3 × 1011 cm−2 、平均高度为 ∼7.1 nm 的 ND。 X 射线光电子能谱 (XPS) 分析表明，远程 H2 等离子体暴露引起硅化反应，同时伴随着 Fe 和 Si 原子在 SiO2 表面的团聚。通过拉曼散射光谱和 XRD 图案测量证实了结晶 β-FeSi2 相的形成。 β-FeSi2 ND 之间的电分离通过点充电导致的表面电位变化得到证实。由于半导体 β-FeSi2 ND 中电子的多步注入和提取，ND 的表面电势相对于尖端电压呈阶梯式变化。
We demonstrated the formation of high-density iron silicide nanodots (NDs) on thermally grown SiO2 by exposing an electron-beam-evaporated Fe/amorphous-Si/Fe (Fe/a-Si/Fe) trilayer stack to remote H2 plasma without any external heating and characterized their silicidation state and crystalline phase. After the remote H2 plasma exposure, the formation of NDs with an areal density of ∼4.3 × 1011 cm−2 and an average height of ∼7.1 nm was confirmed. X-ray photoelectron spectroscopy (XPS) analyses indicate silicidation reaction induced by the remote H2 plasma exposure, which was accompanied by the agglomeration of Fe and Si atoms on the SiO2 surface. The formation of a crystalline β-FeSi2 phase was confirmed by Raman scattering spectroscopy and XRD pattern measurements. The electrical separation among the β-FeSi2 NDs was confirmed from changes in surface potential due to charging of the dots. The surface potential of the NDs changed in a stepwise manner with respect to the tip voltage because of multistep electron injection into and extraction from the semiconductor β-FeSi2 NDs.