Abstract Raman scattering spectroscopy is powerful, express and non-destructive method for control of phase composition of different materials. To determine the crystalline part, one should know the ratio of Raman cross sections of crystalline to amorphous phases. In this Letter we report on accurate comparative measurements of the Raman scattering from monocrystalline and nanocrystalline Ge, as well as from amorphous Ge films. Being accompanied by the respective optical transmittance/reflectance measurements, these data allowed us to estimate the integrated Raman scattering cross section ratios of monocrystalline and nanocrystalline Ge to amorphous Ge, for the first time. For monocrystalline Ge the obtained ratio is equal to 4, while for nanocrystalline Ge this ratio decreased monotonously with a decrease of the nanocrystal sizes. Some physical reasons of the experimentally observed dependence are proposed.

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关于非晶与纳米晶锗的拉曼散射截面比

摘要 拉曼散射光谱是一种控制不同材料相组成的强大、快速和非破坏性的方法。要确定结晶部分，应该知道结晶相与非晶相的拉曼横截面之比。在这封信中，我们报告了对单晶和纳米晶 Ge 以及非晶 Ge 薄膜的拉曼散射的准确比较测量。伴随着各自的光学透射率/反射率测量，这些数据使我们能够首次估计单晶和纳米晶 Ge 与非晶 Ge 的综合拉曼散射截面比。对于单晶Ge，获得的比率等于4，而对于纳米晶Ge，该比率随着纳米晶尺寸的减小而单调减小。