Retardation in the Oxidation Rate of Nanocrystalline Silicon Quantum Dots
Retardation in the Oxidation Rate of Nanocrystalline Silicon Quantum Dots
复制标题
纳米晶硅量子点氧化速率的延迟
DOI：
10.1557/proc-638-f5.3.1
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
S. Oda
中科院分区：
文献类型：
--
作者：
J. Omachi;R. Nakamura;K. Nishiguchi;S. Oda
采用甚高频（VHF）等离子体分解SiH 4和脉冲气体技术，成功制备了平均直径为8 nm、色散为1 nm的纳米硅（nc-Si）量子点。天然氧化物的作用非常重要。它控制nc-Si点的尺寸。特别令人感兴趣的是，这些点的氧化可以是自限制的，由于应力诱导附近的Si/氧化物界面，这将允许进一步减小尺寸和改善分散。本文系统地研究了纳米硅点的氧化过程。将在Ar等离子体中用SiH 4气体脉冲形成的Nc-Si点沉积到Pt网上。然后在750、800和850°C下将点氧化20分钟至15小时。直接从TEM显微照片测量并分析残余nc-Si和生长的氧化物的尺寸。为了比较，场氧化物使用椭圆偏振法进行了研究。观察到nc-Si的氧化速率的延迟。考虑到应力的影响，在nc-Si的氧化速率降低的机制进行了讨论。
Using very-high-frequency (VHF) plasma decomposition of SiH4 and pulsed gas technique, we have successfully prepared nanocrystalline silicon (nc-Si) quantum dots having average diameter of 8 nm and dispersion of 1 nm. The role of natural oxide is very important. It controls the size of nc-Si dots. Of particular interest is that the oxidation of these dots can be self limited, due to the stress induced near Si/oxide interface, which would allow further reduction of size and improvement in dispersion. This paper deals with the systematic study of oxidation process of nc-Si dots. Nc-Si dots formed in an Ar plasma with SiH4 gas pulses are deposited onto a Pt mesh The dots are then oxidized at 750, 800 and 850°C from 20 minutes to 15 hours. The dimensions of the residual nc-Si and the grown oxide are measured directly from the TEM micrographs and analyzed. For comparison, field oxide is investigated using ellipsometry. Retardation in the oxidation rate of nc-Si is observed. The mechanism of the reduction of oxidation rate in nc-Si is discussed taking into account the effect of stress.