Raytheon Company

T Kirk Dougherty

John J Drab

O Glenn Ramer

Steven E Lau

Steven A Tunick

Teresa L Rosales

A temperature-compensated capacitor device has ferroelectric properties and includes a ferroelectric capacitor using a ferroelectric material such as a metal oxide ferroelectric material, a negative-temperature-variable capacitor using a negative-temperature-coefficient-of-capacitance material such as a metal oxide paraelectric material, and an electrical series connection between the negative-temperature-variable capacitor and the ferroelectric capacitor. The temperature-compensated capacitor device may be formed as an integrated layered structure, or as separate capacitors with a discrete electrical connection therebetween.

Temperature-compensated ferroelectric capacitor device, and its fabrication

A water-stable and water-soluble ceramic precursor is provided, containing at least one Group III element. Also, a metal acid salt complex is provided comprising (1) bismuth, lanthanum, and titanium, and (2) a polyether acid. In addition, methods are provided for preparing the Group III metal acid salt complex and the Bi, La, Ti acid salt complex comprising a bismuth polyether acid salt complex, a lanthanum polyether acid salt complex, and a titanium polyether acid salt complex. Finally, devices that include lanthanum-doped bismuth titanate as the active component are provided, as well as a water-stable and water-soluble gallium polyether acid complex.

Water-soluble group III polyether acid salt complexes and thin films from same

The present invention is directed to the synthesis, processing and test of improved spin-on precursor materials comprising at least one Group II metal and at least one Group IV or Group V metal, useful for making thin oxide films, useful, for example, in various electronic devices, such as ferroelectric devices. For example, barium strontium titanate spin-on precursor materials are useful for making thin films of barium strontium titanate (BST) for, e.g., ferroelectric capacitors. A method is provided for fabricating electronic devices employing such Group II-Group IV (or V) oxides as the active device, using polyether acids. The method comprises: (a) providing a substrate; (b) forming a bottom electrode on the substrate; (c) depositing a solution comprising polyether acid salts of the Group II and Group IV or Group V metal ions; (d) forming the oxide film from the solution; and (e) forming a top electrode on the oxide film. As a consequence of the method, improved electronic devices are formed from less toxic and easier handled precursors and solvents. The present invention provides for a soluble spin-on precursor which is compatible and soluble in non-toxic and environmentally benign solvents. In addition, this spin-on precursor material has been shown to give much improved electrical performance properties of the BST thin films produced.

Environmentally benign Group II and Group IV or V spin-on precursor materials

Metal acid salt complexes are provided comprising (1) a first metal ion consisting essentially of bismuth, and optionally, at least one second metal ion selected from the group consisting of barium, calcium, strontium, lead, titanium, tantalum, and niobium, and (2) a polyether acid. The metal acid salt complexes are prepared by combining (1) bismuth ion, and optionally, at least one second metal ion and (2) at least one of a polyether acid and a polyether acid anhydride prepared from the polyether acid. In particular, the use of a mixture of bismuth, strontium, and niobium and/or tantalum salts of the hydrophilic acid 3,6-dioxaheptanoic acid salt is described for production of ceramic thin films, such as for use in ferroelectric devices, using non-toxic solvents. As a consequence, improved electronic devices are formed from less toxic and easier handled precursors and solvents. The present invention provides soluble spin-on precursors which are compatible and soluble in non-toxic and environmentally benign solvents.

Environmentally benign bismuth-containing spin-on precursor materials

The following class of glycidyl and allyl ethers are found to cure at room temperature much faster than their glycidyl and allyl analogs: ##STR1## where: R.sub.1 is selected from the group consisting of:

Aromatic silane ether-containing coatings

Amine adducts comprising a reactive amine curing agent containing an aromatic silane epoxy along with improved coatings made by combining the amine adduct with additional epoxy material. The amine adducts, when formulated and cured with an epoxy material, cures in several hours and gives a protective coating material that cures without blush or CO.sub.2 incorporation. Specific embodiments of the amine adduct contain a bisepoxy compound, such as 2,11-bis(3-glycidylphenyl)-2,11dimethyl-2,11-disiladodocane (n=4), for example, while the amine functionalized compound may be ethylenediamine (90.degree. C., 120.2 g, 20 mol) or aminoethylpiperazine, respectively. A number of chemical compounds are also disclosed.

Amine curing agents and epoxy coatings produced using same

Novel metal acid salt complexes are provided comprising (1) a metal selected from Group IV and Group V metals and (2) a polyether acid, along with a process for making the salt complexes. The process comprises: (a) preparing a polyether acid anhydride from the corresponding polyether acid; and (b) combining a metal alkoxide containing the Group IV or Group V metal with the polyether acid anhydride to form the metal acid salt complex. The resulting Group IV and Group V metal acid salt complexes enable the production of improved thin film, thick film, and bulk ceramic metal oxides and mixed metal oxides for a number of applications, including ferroelectric, electrooptic, paraelectric, and piezoelectric devices, using liquid soluble precursors which are soluble in far less toxic solvents than in the prior art. The soluble ceramic precursors may also be used as reactive binders and shape-forming aids in conventional ceramic processing.

Growing community of inventors

Playa Del Rey, CA, United States of America

T Kirk Dougherty