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 AMPC  Vol.3 No.1 , March 2013
Thickness Dependence of Dielectric Characteristics of SrTiO3 Thin Films on MgAl2O4 Substrates
Abstract: SrTiO3 (STO) thin films of different thicknesses were deposited on MgAl2O4 (MAO) substrates to investigate the in-plane strain effect on the soft-mode frequency of the STO films. X-ray reciprocal space mapping (X-RSM) results indicate that there was no relaxation of the in-plane lattice strain of the STO films on MAO. Shifts in the soft-mode frequencies with a decrease in the film thickness were observed using terahertz time-domain spectroscopy (THz-TDS). However, despite the larger lattice mismatch between STO and MAO than that between STO and DyScO3 (DSO), the shifts in the soft-mode frequencies of the STO films on MAO were smaller than those on DSO. The results indicate that the soft-mode frequencies of the STO films on MAO are affected by the c-axis (out-of-plane) lengths.
Cite this paper: R. Kinjo, I. Kawayama, H. Murakami and M. Tonouchi, "Thickness Dependence of Dielectric Characteristics of SrTiO3 Thin Films on MgAl2O4 Substrates," Advances in Materials Physics and Chemistry, Vol. 3 No. 1, 2013, pp. 58-61. doi: 10.4236/ampc.2013.31009.
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