IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Dielectrics Monday Sessions
       Session DI1-MoP

Paper DI1-MoP21
Structural and Microwave Properties of Artificial BaTiO@sub 3@/SrTiO@sub 3@ Superlattice on MgO and SrTiO@sub 3@ Substrate by Pulsed Laser Deposition

Monday, October 29, 2001, 5:30 pm, Room 134/135

Session: High K Dielectrics Poster Session
Presenter: J.H. Kim, Sungkyunkwan University, Korea
Authors: J.H. Kim, Sungkyunkwan University, Korea
L. Kim, Sungkyunkwan University, Korea
Y.N. Kim, Sungkyunkwan University, Korea
D. Jung, Sungkyunkwan University, Korea
Y.S. Kim, Sungkyunkwan University, Korea
J. Lee, Sungkyunkwan University, Korea
Correspondent: Click to Email
BaTiO@sub 3@ (BTO)/SrTiO@sub 3@ (STO) superlattice has been deposited on MgO and STO substrates by pulsed laser deposition (PLD). BTO/STO superlattice has an epitaxial layer of BTO and STO with the parallel crystallographic orientation to MgO or STO substrates. The periodicity of the BTO/STO superlattice was varied from 0.8 nm thickness to 50 nm and the total thickness of the superlattice was fixed at 100 nm. Structural properties of the superlattice with various periods were examined by X-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM). This superlattice exhibited ferroelectricity in capacitance-voltage (C-V) characteristics, i.e., inverted butterfly hysteresis loop. Asymmetric behavior in C-V characteristics were also observed in the superlattice, which had different bottom and top electrodes each other. For microwave applications, the voltage tunability in the C-V characteristics was measured. The voltage tunability increased with decreasing the period of the superlattice. The tunability reached 90 % at the period of 2 nm. The tunability of BTO/STO superlattice was discussed in terms of periodicity and strain relaxation.