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Thickness Dependence of Dielectric Characteristics of SrTiO3 Thin Films on MgAl2O4 Substrates

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DOI: 10.4236/ampc.2013.31009    3,949 Downloads   5,830 Views   Citations

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.

Conflicts of Interest

The authors declare no conflicts of interest.

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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