Orientation-dependent electro-optical response of BaTiO 3 on SrTiO 3-buffered Si ( 001 ) studied via spectroscopic ellipsometry

To design a high performance BaTiO3 (BTO)-integrated Si modulator, understanding how BTO domain orientations influence its electro-optical (EO) properties is crucial. The 100-nm-thick BTO films with c-oriented and a-oriented domains are obtained by exploiting various thickness of SrTiO3 buffer layers grown on Si(001) substrates. Then, the electro-optical behavior for 2 differently oriented samples is analyzed using spectroscopic ellipsometry. © 2017 Optical Society of America OCIS codes: (160.2660) Ferroelectrics; (160.2100) Electro-optical materials; (190.4400) Nonlinear optics, materials; (310.0310) Thin films; (310.3840) Materials and process characterization; (310.6860) Thin films, optical properties. References and links 1. E. Bousquet, M. Dawber, N. Stucki, C. Lichtensteiger, P. Hermet, S. Gariglio, J. M. Triscone, and P. Ghosez, “Improper ferroelectricity in perovskite oxide artificial superlattices,” Nature 452(7188), 732–736 (2008). 2. C. C. Homes, T. Vogt, S. M. Shapiro, S. 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