硅纳米结构中硅空位缺陷引发的双峰蓝光发射

Blue emission from Si vacancy defects in Si nanostructures

报道了在硅纳米结构中 4 1 7nm和 4 36nm双峰结构的蓝光发射的实验和理论研究结果 .制备了四种包含和没有包含β SiC纳米晶粒的硅纳米结构 ,观察到了 4 1 7nm和 4 36nm的双峰蓝光发射 .光致发光谱的分析和微结构的观察揭示了蓝光发射与硅纳米结构中过剩硅缺陷中心的存在有关 .计算了由过剩硅原子形成的含有硅空位缺陷的纳米晶粒的电子能级 ,发现计算所得的态密度的特征与观察到的双峰发射吻合 .这项工作提出了在许多硅纳米结构中存在 4 1 7nm和 4

We report recent experimental and theoretical results on the blue emission from Si nanostructures. Four groups of Si nanostructures with and without β-SiC nanocrystals were fabricated to clarify the origin of a blue emission with a double-peak structure at 417 and 436 nm. Spectral analyses and microstructural observations show that this blue emission is related to the existence of excess Si atoms in the Si nanostructures. The energy levels of electrons in Si nanocrystals with vacancy defects formed from excess Si atoms are calculated and the characteristics of the density of states coincide with the observed double-peak emission. The present work provides a possible mechanism of the blue emission at 417 and 436 nm in various Si nanostructures.