Min-Su Kwona, Sung-Gap Leea,*, Kyeong-Min Kima and
Seungkeun Choib
aDept. of Materials Engineering and Convergence Technology, ERI,
Gyeongsang National University, Jinju 52828, Korea
bSchool of STEM, Univ. of Washington, Bothell, WA, 98011, USA
In this study, the
multilayered thin films of (Ba,Sr)TiO3/K(Ta,Nb)O3 were
fabricated by the sol-gel and spin coating methods, and their structural and
electrical properties were investigated. The specimen showed polycrystalline
X-ray diffraction (XRD) characteristics with a tetragonal structure. The
average grain size and film thickness for one coating were about 30~40nm and
60nm, respectively. The phase transition temperature of specimen was lower than
10 oC. The dielectric constant and loss at 20 oC
of the specimen coated six times were 1,231 and 0.69, respectively. The rate of
change in dielectric constant at an applied direct current (DC) voltage of the
six times coated thin films was 17.3%/V. The electrocaloric effect was the
highest around the temperature at which the remanent polarization rapidly
changed. When an electric field of 660kV/cm was applied to the triply coated
thin films, the highest electrocaloric property of 4.41 oC was
observed.
Keywords: Ba(Sr,Ti)O3, K(Ta,Nb)O3, Multilayer thin film, Ferroelectric effect, Electro-caloric effect, Remanent polarization, Interface properties.
2019; 20(6): 603-608
Published on Dec 31, 2019
Dept. of Materials Engineering and Convergence
Technology, ERI, Gyeongsang National University, Jinju 52828, Korea
Tel : +82-55-772-1687