MICROSTRUCTURE AND OPTICAL ABSORPTION PROPERTIES OF SI NANOCRYSTALS FABRICATED WITH LOW-PRESSURE CHEMICAL-VAPOR DEPOSITION
MICROSTRUCTURE AND OPTICAL ABSORPTION PROPERTIES OF SI NANOCRYSTALS FABRICATED WITH LOW-PRESSURE CHEMICAL-VAPOR DEPOSITION
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DOI：
10.1063/1.363359
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发表时间：
1996-10
影响因子：
3.2
通讯作者：
A. Nakajima;Y. Sugita;K. Kawamura;H. Tomita;N. Yokoyama
中科院分区：
文献类型：
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作者：
A. Nakajima;Y. Sugita;K. Kawamura;H. Tomita;N. Yokoyama
我们报告了一种在 SiO2 玻璃基板上制造一层孤立的硅量子点的简单技术。该技术采用传统的低压化学气相沉积，在多晶硅薄膜生长的早期阶段沉积时间极短。沉积时间为 60 秒后，该层已分离出直径为 5-20 nm、高度为 2-10 nm 的硅纳米晶体。光吸收系数α的测量表明，与块体硅相比，硅纳米晶的吸收边移动到更高的能量，这表明量子尺寸效应引起的能隙变宽。 (αhν)1/2与hν的线性关系表明，直径小至10 nm的Si纳米晶基本上保持了间接带隙半导体的特性。制造硅量子点时必须特别注意硅纳米晶的布朗迁移。
We report a simple technique for fabricating a layer of isolated Si quantum dots on SiO2 glass substrates. This technique uses conventional low‐pressure chemical‐vapor deposition for an extremely short deposition time in the early stage of poly‐Si film growth. The layer after a deposition time of 60 s has isolated Si nanocrystals 5–20 nm in diameter and 2–10 nm in height. The measurements of optical absorption coefficient α show that the absorption edge for Si nanocrystals shifts to higher energies compared to that of bulk Si, indicating a widening of the energy gap caused by quantum size effects. The linear relationship (αhν)1/2 against hν suggests that the Si nanocrystal, whose diameter is as small as 10 nm, basically maintains the properties of an indirect band‐gap semiconductor. Special attention must be paid to the Brownian migration of Si nanocrystals for fabricating Si quantum dots.