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系统研究了a SiOx 的Raman散射谱及其退火行为 ,并通过退火技术使Si从SiOx 网络中分凝出来 ,形成纳米硅和SiO2 的镶嵌结构 .并利用Raman散射技术研究了这种复合薄膜中纳米硅的声子态 .发现在 1 0 0～ 6 0 0cm-1的波数范围内 ,纳米硅的Raman谱可用 5条Lorentz线得到很好地拟合 ,并对这 5条线的来源作了确认 ;观测到了在 6 0 0～ 1 1 0 0cm-1范围内纳米硅的双声子散射 .研究结果表明 ,镶嵌在SiO2 介质中的纳米硅具有非晶硅相和纳米硅晶相共存的特点 ,两者均对Raman散射有贡献 .不仅观测到了声子限制效应使一级光学声子频率随纳米硅晶粒尺寸减小而红移这一现象 ,而且还发现 (与体硅相比 )声子限制效应对二级Raman散射具有增强效应 ,并对二级散射模的频率也会产生影响 .
The Raman scattering spectra of a SiOx and its annealing behavior were systematically studied and the Si was separated from the SiOx network by annealing to form a damascene structure of nanosilica and SiO2. The Raman scattering It is found that the Raman spectrum of nanosilica can be fit well with five Lorentz lines in the wavenumber range of 100 ~ 600cm-1, and the sources of these five lines have been confirmed The diatomic phonon scattering of nanosilica in the range of 600 ~ 110cm-1 was observed.The results show that the nanosilica embedded in SiO2 has the characteristic of the coexistence of amorphous silicon and nanocrystalline silicon, All contributed to the Raman scattering.Not only the phenomenon of phonon confinement was observed to red shift the first-order optical phonon frequency with the decrease of nanocrystalline silicon grain size, but also the phonon confinement (compared with bulk silicon) was found The effect has an enhancement effect on the second-order Raman scattering and also affects the second-order scattering mode’s frequency.