Stock material or miscellaneous articles – Composite – Of metal
Patent
1995-06-07
1999-03-30
Speer, Timothy
Stock material or miscellaneous articles
Composite
Of metal
428472, 428689, 428697, 428701, 428702, B32B 1700
Patent
active
058886591
ABSTRACT:
The invention forms improved ferroelectric (or pyroelectric) material by doping an intrinsic perovskite material having an intrinsic ferroelectric (or pyroelectric) critical grain size with one or more donor dopants, then forming a layer of the donor doped perovskite material having an average grain size less than the intrinsic ferroelectric (or pyroelectric) critical gran size whereby the remanent polarization (or pyroelectric figure of merit) of the layer is substantially greater than the remanent polarization (or pyroelectric figure of merit) of the intrinsic perovskite material with an average grain size similar to the average grain size of the layer. The critical ferroelectric (or pyroelectric) grain size, as used herein, means the largest grain size such that the remanent polarization (or pyroelectric figure of merit) starts to rapidly decrease with decreasing grain sizes. Preferably, the donor doped perovskite material is further doped with one or more acceptor dopants to form a donor acceptor doped perovskite material whereby the resistivity is substantially increased. Preferably, the intrinsic perovskite material has a chemical composition AB03, where A is one or more monovalent, divalent or trivalent elements, and B is one or more pentavalent, tetravalent, trivalent or divalent elements. Structures containing an improved ferroelectric (or pyroelectric) material include a layer of donor doped perovskite material with average grain size less than the intrinsic ferroelectric (or pyroelectric) critical grain size formed on the surface of a substrate. Other structures include such a layer of donor doped material interposed between two electrically conducting layers.
REFERENCES:
patent: 3975307 (1976-08-01), Matsuo
patent: 3996168 (1976-12-01), Hoffmann
patent: 4024081 (1977-05-01), Ohmori et al.
patent: 4059537 (1977-11-01), Espinosa
patent: 4101454 (1978-07-01), Kulwicki
patent: 5130281 (1992-07-01), Sano et al.
patent: 5202814 (1993-04-01), Kohno et al.
patent: 5268006 (1993-12-01), Ueno
patent: 5314651 (1994-05-01), Kulwicki
patent: 5453262 (1995-09-01), Dawson
Wang, et al. "The Effect of Dysprosium On The Microstructure and Dielectric Properties of (Ba.sub.1x Sr.sub.x)TiO.sub.3 " ISAF Proceedings, pp. 55-58, '92.
Kumar et al. "Grain Size Effect on the Dielectric Properties of Strontium Barium Titanate", ISAF Proceedings, pp 55-58, '92.
Dy-Doped BaTiO.sub.3 Ceramics for High Voltage Capacitor Use, Murakami, et
A Modified Barium, Titanate for Capacitors, U. Syamaprasad, et al. J. Am
Ceramic Materials for Electronics, I. Buchanan, II Series.
Dependence of the Crystal Structure on Particle Size in Barium Titanate, Kenji Uchino, et al., Communications of the American Ceramic, Aug. 1989, 1555-1558.
Beratan Howard R.
Kulwicki Bernard M.
Summerfelt Scott R.
Donaldson Richard L.
Harris James E.
Speer Timothy
Stoltz Richard A.
Texas Instruments Incorporated
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