US Government As Represented by the Secretary of the Army

Daniel M Potrepka

Steven C Tidrow

Arthur Tauber

Ronald G Polcawich

Glen Richard Fox

Frank J Crowne

Luz M Sanchez

Bernard J Rod

James R Mulcahy

A method of making a piezoelectric device comprising providing a deposition chamber, the deposition chamber having reduced pressure therein; loading a substrate into the deposition chamber; sputter depositing hexagonal 001 oriented titanium on the substrate; providing an oxygen anneal to convert 001 oriented titanium into 100 oriented rutile TiO; sputter depositing a 111 or 100 oriented textured conducting material for use as an electrode; sputter depositing a hexagonal 001 oriented titanium and providing an oxygen anneal in a lead oxide environment to convert 001 oriented titanium into 100 oriented rutile TiOor PbTiO; sputter depositing textured lead zirconate titanate PbZrTiOhaving an 001 orientation as a piezoelectric layer, and sputter depositing a textured electrode on top of the textured lead zirconate titanate; whereby processing of the layers within the deposition chamber provides minimized exposure to ambient contamination and improved texturing in the resulting films.

Process for making lead zirconate titanate (PZT) layers and/or platinum electrodes and products thereof

A ferroelectric device comprising a substrate; a textured layer; a first electrode comprising a thin layer of metallic material having a crystal lattice structure divided into granular regions; a seed layer; the seed layer being epitaxially deposited so as to form a column-like structure on top of the granular regions of the first electrode; at least one ferroelectric material layer exhibiting spontaneous polarization epitaxially deposited on the seed layer; the ferroelectric material layer, the seed layer, and first electrode each having granular regions in which column-like structures produce a high degree of polarization normal to the growth plane and a method of making.

Stylo-epitaxial piezoelectric and ferroelectric devices and method of manufacturing

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 method for forming an electrical device having a {100}-textured platinum electrode comprising: depositing a textured metal thin film onto a substrate; thermally oxidizing the metal thin film by annealing to convert it to a rocksalt structure oxide with a {100}-texture; depositing a platinum film layer; depositing a ferroelectric film. An electrical device comprising a substrate; a textured layer formed on the substrate comprising metal oxide having a rocksalt structure; a first electrode film layer having a crystallographic texture acting as a template; and at least one ferroelectric material layer exhibiting spontaneous polarization epitaxially deposited on the first electrode film layer whereby the rocksalt structure of the textured layer facilitates the growth of the first electrode film layer with a {100} orientation which forms a template for the epitaxial deposition of the ferroelectric layer such that the ferroelectric layer is formed with an {001} orientation.

Thermally oxidized seed layers for the production of {001} textured electrodes and PZT devices and method of making

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

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

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

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.

Growing community of inventors

Silver Spring, MD, United States of America

Daniel M Potrepka