Walter J Symes

20080063881, Mar 13, 2008

Sep 13, 2006

10/599925

Walter J. Symes - Dundee NY, US
Mohammed H. Megherhi - Victor NY, US
Elisabeth W.J. Romer - LD Uden, NL
Mike S.H. Chu - Lewiston NY, US
Wilibrordus J.L.M.J Coppens - WL Uden, NL

C04B 35/00
B32B 15/04
C03B 25/00

428457, 501135, 65120, 65 62

Multilayer ceramic chip capacitors which satisfy COG requirements and which are compatible with reducing atmosphere sintering conditions so that non-noble metals such as nickel and nickel alloys thereof may be used for internal and external electrodes are made in accordance with the invention. The capacitors exhibit desirable dielectric properties (high capacitance, low dissipation factor, high insulation resistance), excellent performance on highly accelerated life testing, and very good resistance to dielectric breakdown. The dielectric layers comprise a strontium zirconate matrix doped with other metal oxides such as TiO, MgO, BO, CaO, AlO, SiO, and SrO in various combinations.

20080218935, Sep 11, 2008

Mar 5, 2007

11/681796

Walter J. Symes - Dundee NY, US
Mike S.H. Chu - Lewiston NY, US

Ferro Corporation - Cleveland OH

H01G 4/30
H01B 3/12

3613014, 25251952

Multilayer ceramic chip capacitors which satisfy X7R and BX requirements and which are compatible with silver-palladium internal electrodes are made in accordance with the invention. The capacitors exhibit desirable dielectric properties (high capacitance, low dissipation factor, high insulation resistance), excellent performance on highly accelerated life testing, and very good resistance to dielectric breakdown. The dielectric layers comprise a lead-free and cadmium-free barium titanate base material doped with other metal oxides such oxides of zinc, boron, bismuth, cerium, tungsten, copper, manganese, neodymium, niobium, silver, barium, silicon and nickel in various combinations. The dielectric ceramic materials herein can be sintered together (fired) at less than 1000 C. with an inner electrode having more than 80 wt % Ag and less than 20 wt % Pd to form a multilayer ceramic capacitor (MLCC).

57831653, Jul 21, 1998

Jan 8, 1997

8/780497

James M. Wilson - Victor NY
Walter J. Symes - Dundee NY

Ferro Corporation - Cleveland OH

C01G 2300

423598

The present invention provides a new and improved method of making barium titanate powder. The method includes the steps of providing a solution comprising oxalic acid and titanium oxychloride, maintaining the solution at a predetermined temperature, adding barium carbonate to the solution thereby precipitating barium titanyl oxalate, and calcining the barium titanyl oxalate so as to provide the barium titanate powder.

55997570, Feb 4, 1997

Oct 26, 1995

8/548710

James M. Wilson - Victor NY
Walter J. Symes - Dundee NY

Ferro Corporation - Cleveland OH

C04B 35468
H01G 410

501137

A low temperature fired NPO type ceramic dielectric composition is employed for making high frequency multi-layer capacitors having dielectric constants between 25 and 40 at room temperature, and which do not vary from this base line value by more than. +-. 30 parts per million (PPM)/. degree. C. over a temperature range of -55. degree. C. to +125. degree. C. with the value at +25. degree. C. being the reference point. The dielectric composition is made from a base dielectric ceramic formulation and a low melting point glass formulation, each derived from metal oxides or precursors thereof. Manganese dioxide or a precursor thereof may be added in the amount of from about 0. 012 to 0. 060 weight percent as the dioxide based on the combined weight of the ceramic formulation and the glass formulation. The mixtures, when made into multi-layer ceramic capacitors (MLCC), are fired at or below 1120. degree. C.

55717675, Nov 5, 1996

Aug 21, 1995

8/517737

James M. Wilson - Victor NY
Walter J. Symes - Dundee NY

Ferro Corporation - Cleveland OH

C04B 3546

501139

Multi-layer ceramic capacitors are made from novel low temperature fired ceramic dielectric compositions which may have dielectric constants of over 3200 at room temperature, and which do not vary in value by more than 15 percent over a temperature range of -55. degree. C. to +125. degree. C. , with the value at +25. degree. C. being the reference point. The compositions comprise a base ceramic formulation or host material, a ceramic sintering aid, and a low melting point glass formulation, each derived from metal oxides or precursors thereof. The host material is made from 97. 89 to 98. 19 weight percent barium titanate and from about 1. 81 to 2. 11 weight percent neodymium oxide, the sintering aid from Bi. sub. 2 O. sub. 3. multidot. 2TiO. sub. 2, and the the glass formulation from 86. 0 wt. % PbO, 9. 0 wt. % B. sub. 2 O. sub. 3, 1. 58 wt. % SiO. sub. 2, 0. 13 wt. % TiO. sub. 2 and 3. 29 wt. % Al. sub. 2 O. sub. 3.