US Government As Represented by the Secretary of the Army

Other

Steven C Tidrow

Arthur Tauber

William D Wilber

Robert D Finnegan

Donald W Eckart

Daniel M Potrepka

William C Drach

Meimei Tidrow

Ernest Potenziani, Ii

Robert A Lux

Frank J Crowne

Bernard J Rod

Romeo D Del Rosario, Jr

James A Harvey

A method and apparatus for obtaining dielectric constant and other measurements of a sample, comprising an open cavity resonator; a microwave energy generator for creating a resonating microwave in the open cavity resonator; a predetermined dielectric material having a high dielectric constant in the range of 2 to 100,000 substantially filling the region in which a microwave resonates; the dielectric material adapted to receive a sample for measurement of the dielectric properties of the sample; whereby during operation the resonating microwave beam is substantially immersed in the predetermined dielectric material such that the effective electrical spot size and beam cross-section along the cylindrical axis of the resonating microwave is reduced as a function of the inverse of the square root of the predetermined dielectric material dielectric constant. The dielectric constant or loss tangent of the sample may be determined based upon the change in the cavity's resonant frequency modes.

Microwave cavity with dielectric region and method thereof

A detector for electromagnetic radiation such as millimeter wave and infrared employs a ring-shaped ferroelectric element having a temperature affected by an absorber for the radiation. The dielectric constant of the ferroelectric material is a strong function of the temperature near its Curie temperature. The resonant frequency of the ferroelectric element is detected by applying a swept-frequency signal to the circuit and detecting the frequency which enhances the energy of the pulse. A two-dimensional camera for the radiation employs a two-dimensional array of these ferroelectric resonant circuits and a system for rapidly interrogating their resonant frequencies on a sequential basis.

Ferroelectric radiation detector employing frequency modulated readout

Rare earth metal containing compounds of the formula SrYbSbOhave been prepared with high critical temperature thin film superconductor structures, and can be fabricated into a superconductor insulator superconductor step edge Josephson junction, as well as being used in other ferroelectrics, pyroelectrics, and hybrid device structures.

Rare earth metal compounds for use in high critical temperature Josephson junctions

Rare earth metal containing compounds of the formula SrLuSbOand SrLaSbOhave been prepared as high critical temperature thin film superconductor structures, and can be used in other ferroelectrics, pyroelectrics, piezoelectrics, and hybrid device structures.

Rare earth metal compounds for use in high critical temperature thin film super-conductors

Rare earth metal containing compounds of the general formula SrRESbO, wherein RE is a rare earth metal, have been prepared as dielectric substrates and buffer layers in thin film superconductor structures, and can be used in other ferroelectrics, pyroelectrics, piezoelectrics, and hybrid device structures.

Rare earth metal compounds for use in high critical temperature thin film structures for super-conductors, ferroelectrics, pyroelectrics, piezoelectrics, and hybrids

Rare earth metal containing compounds of the formula SrLuSbOhave been prepared with high critical temperature thin film superconductor structures, and can be fabricated into an antenna, as well as being used in other ferroelectrics, pyroelectrics, piezoelectrics, and hybrid device structures.

Rare earth metal compounds for use in high critical temperature thin film super-conducting antennas

Single-phase, non-cubic and single-phase, cubic ferroelectric/paraelectric perovskite-structured materials having reasonably low and fairly temperature insensitive dielectric constants (stable dielectric constants over a wide range of operating temperatures of &#x2212;80&#xb0; C. to 100&#xb0; C.), reasonable loss tangents (&#x3c;&#x2dc;10), high tunability, and significantly lowered Curie temperature below the temperature range of operation for previous undoped perovskite structures are provided. The FE/PE materials of the present invention have dilute charge-compensated substitutions in the Ti site of the perovskite structure. This single-phase structure or a variant of it with a Ti rich composition, provided herein, allows for pulsed-laser-deposition of a thin film with uniform transfer of the structure of the target into the deposited film, which enables production of very small, lightweight devices that are extremely efficient and consume little power. These ferroelectric/paraelectric materials may be used in phase shifter devices (such as used in cell phones, antennas and the like), variable true time delay devices, steerable beams, tunable filters, impedance transformers, variable control oscillators, antennas, radios, filters, microwave variable capacitors, radar systems, electronic warfare sensors, resonators, microwave transverse-electromagnetic-ferroelectric voltage-controlled oscillators, and other RF, microwave, or millimeter wave tunable devices for synthesizers and systems incorporating all of the above, as well as any application that enhances the performance of various types of electrical and electro-optic devices.

Ferroelectric/paraelectric materials, and phase shifter devices, true time delay devices and the like containing same

A method of fabricating a colossal magneto-resistive detector using a thin film transfer method includes the use of a perovskite oxide material as a substrate, and a rock salt structure material as a buffer layer, template layer, and release layer. Advantages associated with the method include not only the ability to produce a detector of the requisite film quality, but one which satisfies the temperature coefficient of resistance and fabrication temperature constraints. In addition, when employed as either the substrate or the buffer layer, template layer, and release layer, after bonding the rock salt structure material can be easily removed using water, and the excess rock salt structure material/water solution can then be removed with known techniques.

Method of fabricating a colossal magneto-resistive detector using a thin film transfer method

Single-phase, non-cubic and single-phase, cubic ferroelectric/paraelectric lead-based perovskite-structured materials having reasonably low and fairly temperature insensitive dielectric constants (stable dielectric constants over a wide range of operating temperatures of &#x2212;80&#xb0; C. to 100&#xb0; C.), reasonable loss tangents (&#x3c;&#x2dc;10), high tunability, and significantly lowered Curie temperature below the temperature range of operation for previous undoped perovskite structures are provided. The FE/PE materials of the present invention have dilute charge-compensated substitutions in the Ti site of the perovskite structure. This single-phase structure or a variant of it with a Ti rich composition, provided herein, allows for pulsed-laser-deposition of a thin film with uniform transfer of the structure of the target into the deposited film, which enables production of very small, lightweight devices that are extremely efficient and consume little power. These ferroelectric/paraelectric materials may be used in phase shifter devices (such as used in cell phones, antennas and the like), variable true time delay devices, steerable beams, tunable filters, impedance transformers, variable control oscillators, antennas, radios, filters, microwave variable capacitors, radar systems, electronic warfare sensors, resonators, microwave transverse-electromagnetic-ferroelectric voltage-controlled oscillators, and other RF, microwave, or millimeter wave tunable devices for synthesizers and systems incorporating all of the above, as well as any application that enhances the performance of various types of electrical and electro-optic devices.

Apparatus for the precise positioning of a sample of dielectric material into a cavity resonator system for obtaining dielectric constant, and other measurements. Precision micrometer drive units are provided to move the sample about a vertical axis, to tilt the sample, and to move the sample in X, Y and Z directions. The drive units are positioned on a bearing slide for ease of sample positioning into and out of the cavity. Selected drive units are controllable from a remote location so that the apparatus may be utilized in an environmental chamber whereby measurements may be accomplished without opening the chamber after each measurement. All components of the resonator system, positioning units, cables, etc. are chosen such that they are operable over the desired temperature range of operation.

Apparatus for precision measurement of microwave material properties as functions of temperature and frequency

Rare earth metal containing compounds of the general formula Sr RESbO , wherein RE is a rare earth metal, have been prepared with high critical temperature thin film superconductor strucutures, and can be used in other ferroelectrics, pyroelectrics, piezoelectrics, and hybrid device structures.

Rare earth metal compounds for use in high critical temperature thin film super-conductors, ferroelectrics, pyroelectrics, piezoelectrics, and hybrids

Single-phase, non-cubic and single-phase, cubic ferroelectric/paraelectric materials comprising a charge compensated lead-based perovskite having the general formula ABO is provided, which has reasonably low and fairly temperature insensitive dielectric constants over operating temperatures of &minus;80&deg; C. to 100&deg; C., reasonable loss tangents (<&tilde;10 ), and high tunability. The FE/PE materials of the present invention have dilute charge-compensated substitutions in the Ti site of the perovskite structure. These ferroelectric/paraelectric materials may be used in phase shifter devices (such as used in cell phones, antennas and the like), variable true time delay devices, steerable beams, tunable filters, impedance transformers, variable control oscillators, antennas, radios, filters, microwave variable capacitors, radar systems, electronic warfare sensors, resonators, microwave transverse-electromagnetic-ferroelectric voltage-controlled oscillators, and other RF, microwave, or millimeter wave tunable devices for synthesizers and systems incorporating all of the above, as well as any application that enhances the performance of various types of electrical and electro-optic devices.

A method of fabricating a colossal magneto-resistive detector using a thin film transfer method includes the use of a rock salt structure material as a substrate. In a second embodiment, the method includes the use of a perovskite oxide material as the substrate, and the rock salt structure material as a buffer layer, template layer, and release layer. Advantages associated with the method include not only the ability to produce a detector of the requisite film quality, but one which satisfies the temperature coefficient of resistance and fabrication temperature constraints. In addition, when employed as either the substrate or the buffer layer, template layer, and release layer, after bonding the rock salt structure material can be easily removed using water, and the excess rock salt structure material/water solution can then be removed with known techniques.

Method of fabricating uncooled IR detector and arrays using colossal magneto-resistive materials and rock salt structure material substrates

A method of fabricating an uncooled ferroelectric/pyroelectric infrared detector having a semi-transparent electrode material includes using a lattice matched substrate material and a crystallographically oriented bottom electrode material as a template for the growth of a crystallographically oriented ferroelectric/pyroelectric film. In a second preferred embodiment, the method includes fabricating a detector assembly, inverting the assembly, and attaching the inverted assembly to a circuit. This embodiment avoids temperature processing constraints associated with the circuit, and thus facilitates the use of higher growth temperatures. Advantages associated with the embodiments of the present invention include the ability to fabricate a crystallographically oriented bottom electrode material as a template for the growth of a crystallographically oriented ferroelectric/pyroelectric film. Furthermore, once the fabrication is complete, the substrate upon which the electrode is deposited can be easily removed. Finally, by virtue of the crystallographically oriented ferroelectric/pyroclectric film, a significant improvement in the overall performance of the detector, and thus in a device such as a focal plane array, is achieved.

Method of fabricating a ferroelectric/pyroelectric infrared detector using a crystallographically oriented electrode and a rock salt structure material substrate

A ferroelectric/pyroelectric infrared detector includes a lattice matched substrate material and a colossal magneto-resistive electrode material. In a second embodiment, the ferroelectric/pyroelectric detector includes a colossal magneto-resistive template material to accommodate the use of a non-lattice matched substrate material, and a colossal magneto-resistive electrode material. The embodiments of the present invention provide a semi-transparent electrode material of the requisite lattice constant value, crystal orientation, and chemical compatibility. Additional advantages associated with the invention include the ability to provide the desired resistance behavior by varying the composition of the colossal magneto-resistive material, the ability to tune the colossal magneto-resistive transition temperature to be near the device operating temperature through appropriate selection of materials and process conditions, and the ability to ensure the crystal oriented growth of the ferroelectric/pyroelectric thin film. By selecting an appropriate colossal magneto-resistive electrode material, the performance of the ferroelectric/pyroelectric detector can be improved over that associated with the use of conventional electrodes such as &ldquo;normal&rdquo; metals or metal oxides.

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Silver Spring, MD, United States of America

Steven C Tidrow