AVS 47th International Symposium
    Dielectrics Thursday Sessions
       Session DI+EL+MS-ThA

Paper DI+EL+MS-ThA7
Epitaxial (Ba,Sr)TiO@sub 3@ on MgO for Room Temperature Microwave Phase Shifters

Thursday, October 5, 2000, 4:00 pm, Room 312

Session: High K Dielectrics: Perovskites
Presenter: C.L. Chen, University of Houston
Authors: C.L. Chen, University of Houston
J. Shen, University of Houston
S.Y. Chen, University of Houston
C.W. Chu, University of Houston
F.W. Van Keuls, NASA Glenn Research Center
F. Miranda, NASA Glenn Research Center
J.C. Jiang, Louisiana State University
Correspondent: Click to Email
Single crystalline ferroelectric Ba@sub 0.6@Sr@sub 0.4@TiO@sub 3@ thin films were epitaxially grown on (001) MgO by using pulsed laser ablation. Microstructure studies from x-ray diffraction and electron microscopy suggest that the as-grown films are c-axis oriented with their interface relationship of <100>@sub BSTO@//<100>@sub MO@. Edge dislocations were found through the entire interface in every 8 unit cell length. Microwave property measurements indicated that the room temperature coupled microwave phase shifter have achieved with phase shift over 200@super o@ at 23.675 GHz and a figure of Merit of about 55@super o@/dB. The room temperature dielectric constant and loss tangent were found to be 1688 and 0.008 and the tunability was 33% with 2.5V/µm. The result suggests that the performance of microwave phase shifter based on the epitaxial ferroelectric thin films on (001) MgO are closed to the practical applications in the wireless rf communications.