Quantum confinement and recombination dynamics in silicon nanocrystals embedded in Si/SiO2 superlattices
Quantum confinement and recombination dynamics in silicon nanocrystals embedded in Si/SiO2 superlattices
复制标题
嵌入 Si/SiO2 超晶格中的硅纳米晶体的量子限制和复合动力学
DOI：
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发表时间：
2000
期刊：
影响因子：
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通讯作者：
C. Spinella
中科院分区：
文献类型：
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作者：
V. Vinciguerra;G. Franzò;F. Priolo;F. Iacona;C. Spinella
在本研究中，对纳米晶 Si/SiO2 超晶格的结构和光学性质进行了研究和讨论。通过对等离子体增强化学气相沉积制备的十周期非晶 Si/SiO2 超晶格进行热退火，形成了硅纳米晶体 (Si-nc) 的有序平面阵列。当退火温度不超过 1200°C 时，超晶格的热处理会产生良好分离的纳米晶硅层（约 5 nm 的 SiO2）。这些层的光致发光（PL）特性已被详细研究。研究发现 PL 峰值波长取决于激光泵浦功率；这种有趣的依赖性，即功率增加时明显的蓝移，已被解释为较大的 Si-nc 具有更长的寿命。还观察到，这些衰变寿命表现出超过两个数量级的单指数行为，与观察到的典型非单指数趋势形成鲜明对比……
In this study the structural and optical properties of nanocrystalline Si/SiO2 superlattices have been investigated and discussed. Ordered planar arrays of silicon nanocrystals (Si-nc) have been formed by thermal annealing of ten period amorphous Si/SiO2 superlattices prepared by plasma enhanced chemical vapor deposition. Thermal processing of the superlattices results in well separated (by about 5 nm of SiO2) nanocrystalline Si layers, when the annealing temperature does not exceed 1200 °C. The photoluminescence (PL) properties of these layers have been studied in details. The PL peaks wavelength has been found to depend on the laser pump power; this intriguing dependence, consisting in a marked blueshift for increasing power, has been explained in terms of the longer lifetime characterizing larger Si-nc. It is also observed that these decay lifetimes exhibit a single exponential behavior over more than two orders of magnitude, in clear contrast with the typical, nonsingle exponential trends observed for...