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Title: Fabrication and characterization of BSTO and nonferroelectric oxide composites for use in phased array antennas and other electronic devices

Abstract

A ceramic ferroelectric phase shifting device has been demonstrated using Ba(1-x)Sr(x)TiO3 (BSTO) ceramics. As a part of an effort to optimize the electronic device performance in the phase shifter, various composites of BSTO combined with other nonelectrically active oxide ceramics have been formulated. In general, the composites have reduced dielectric constants, epsilon`, where epsilon = epsilon` = i(epsilon)`, and loss tangents, tan delta. The low dielectric constant and low loss tangent reduce the overall impedance mismatch and the insertion loss of the device, In addition, the overall tunability, change in the dielectric constant with applied voltage, is maintained at a relatively high level. The combination of electronic properties of these materials offer substantially higher operating frequencies, 10 GHz and above. Another application for one of the composites is for use as a capacitor-varistor surge protector. The microstructures including grain size and phase analysis have been examined using SEM and X-ray diffraction. The analysis of the phase formation, compositional variations, and grain size will be related to the electronic properties of the materials.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Army Research Lab., Watertown, MA (United States)
OSTI Identifier:
91469
Report Number(s):
AD-A-290070/2/XAB; ARL-TR-652
TRN: 52261188
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: Dec 1994
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; BARIUM OXIDES; FABRICATION; DIELECTRIC PROPERTIES; STRONTIUM OXIDES; TITANIUM OXIDES; COMPOSITE MATERIALS; MICROSTRUCTURE; ANTENNAS; CERAMICS

Citation Formats

Sengupta, L.C., Ngo, E., O`Day, M.E., Stowell, S., and Lancto, R. Fabrication and characterization of BSTO and nonferroelectric oxide composites for use in phased array antennas and other electronic devices. United States: N. p., 1994. Web.
Sengupta, L.C., Ngo, E., O`Day, M.E., Stowell, S., & Lancto, R. Fabrication and characterization of BSTO and nonferroelectric oxide composites for use in phased array antennas and other electronic devices. United States.
Sengupta, L.C., Ngo, E., O`Day, M.E., Stowell, S., and Lancto, R. 1994. "Fabrication and characterization of BSTO and nonferroelectric oxide composites for use in phased array antennas and other electronic devices". United States. doi:.
@article{osti_91469,
title = {Fabrication and characterization of BSTO and nonferroelectric oxide composites for use in phased array antennas and other electronic devices},
author = {Sengupta, L.C. and Ngo, E. and O`Day, M.E. and Stowell, S. and Lancto, R.},
abstractNote = {A ceramic ferroelectric phase shifting device has been demonstrated using Ba(1-x)Sr(x)TiO3 (BSTO) ceramics. As a part of an effort to optimize the electronic device performance in the phase shifter, various composites of BSTO combined with other nonelectrically active oxide ceramics have been formulated. In general, the composites have reduced dielectric constants, epsilon`, where epsilon = epsilon` = i(epsilon)`, and loss tangents, tan delta. The low dielectric constant and low loss tangent reduce the overall impedance mismatch and the insertion loss of the device, In addition, the overall tunability, change in the dielectric constant with applied voltage, is maintained at a relatively high level. The combination of electronic properties of these materials offer substantially higher operating frequencies, 10 GHz and above. Another application for one of the composites is for use as a capacitor-varistor surge protector. The microstructures including grain size and phase analysis have been examined using SEM and X-ray diffraction. The analysis of the phase formation, compositional variations, and grain size will be related to the electronic properties of the materials.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 1994,
month =
}

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