Understanding the optical anisotropy of oxidized Si(001) surfaces
نویسندگان
چکیده
First-principles optical-response calculations of oxidized and strained Si structures are presented. Local Si lattice deformations accompanying the oxidation of Si bulk bonds cause pronounced optical anisotropies that account very well for the reflectance difference signal measured during oxide growth Yasuda et al., Phys. Rev. Lett. 87, 037403 2001 . In contrast, calculations for various energetically favored 4 2 and 2 2 reconstructed overlayer structures fail to reproduce the experiment.
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