Substrate dependence of adlayer optical response in reflectance anisotropy spectroscopy
Substrate dependence of adlayer optical response in reflectance anisotropy spectroscopy
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反射各向异性光谱中吸附层光学响应的基底依赖性
DOI：
10.1116/1.581464
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发表时间：
1998
期刊：
影响因子：
--
通讯作者：
P. Weightman
中科院分区：
文献类型：
--
作者：
R. Cole;B. Frederick;P. Weightman
反射各向异性光谱（RAS）具有极高的表面灵敏度，可用于研究气-固和固-液界面。虽然该技术已经作出了相当大的贡献，在原位监测的外延生长的半导体，其影响到目前为止，在解释实验结果的困难受到限制。特别地，RAS谱与Δe2′和Δe2“（表面介电各向异性的真实的和虚部）两者相关，其中权重因子由衬底的复介电函数确定。在这里RAS计算进行各种基板假设模型覆盖层介电各向异性。观察到三种不同的行为：RAS光谱可以类似于Δe2′，Δe2″或−Δe2″（或三者的某种组合），这取决于衬底和光子能量。因此，它是至关重要的，以适当地考虑这些基板的影响，如果RAS是用来确定方位角取向的adso…
Reflectance anisotropy spectroscopy (RAS) offers extreme surface sensitivity and can be used to study gas-solid and solid-liquid interfaces. Although the technique has already made a considerable contribution to in situ monitoring of the epitaxial growth of semiconductors, its impact has thus far been limited by difficulties in interpreting experimental results. In particular, RAS spectra are related to both Δe2′ and Δe2″, the real and imaginary parts of the surface dielectric anisotropy, with weighting factors determined by the complex dielectric function of the substrate. Here RAS calculations are performed for a variety of substrates assuming a model overlayer dielectric anisotropy. Three distinct regimes of behavior are observed: RAS spectra can resemble either Δe2′, Δe2″ or −Δe2″ (or some combination of the three) depending on the substrate and the photon energy. It is therefore crucial to properly account for these substrate effects if RAS is to be used to determine the azimuthal orientation of adso...