Thomas W Dougherty

US Patent:

6984745, Jan 10, 2006

Filed:

Feb 2, 2004

Appl. No.:

10/771066

Inventors:

Thomas K. Dougherty - Playa Del Rey CA, US
John J. Drab - Santa Barbara CA, US

Assignee:

Raytheon Company - Waltham MA

International Classification:

C07F 3/00
C07F 7/00
C04B 35/49
B05D 5/12
C09K 3/00

US Classification:

556 55, 556105, 501134, 4271263, 423608, 423618, 25218311

Abstract:

The synthesis, processing and test of improved lead zirconate titanate (PZT) precursor materials useful for making bulk, thick films and thin films of PZT are provided. PZT is an oxide ceramic extensively used for its piezoelectric properties. A variety of devices made from piezoelectric PZT are known. A soluble spin-on precursor is provided that is compatible with and soluble in non-toxic and environmentally benign solvents (including water), has high stability and long shelf life, and provides high quality PZT films.

US Patent:

8007989, Aug 30, 2011

Filed:

Apr 11, 2008

Appl. No.:

12/081143

Inventors:

Thomas Kirk Dougherty - Playa Del Rey CA, US

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

G03F 7/00
G03F 1/00

US Classification:

430322, 430325, 430330

Abstract:

A method for forming a patterned ferroelectric layer, having ferroelectric electronic properties, on a substrate. A composite layer, made of ferroelectric layer producing metal acrylate compounds, a photoinitiator compound and an acrylate crosslinking compound is formed on the substrate. A photomask is formed on the composite layer. Unmasked areas of the composite layer are irradiated with ultraviolet light. A solvent removes non-irradiated areas of the composite layer from the substrate. The patterned composite layer is heated in an oxygen atmosphere to cause a chemical reaction among the ferroelectric layer producing metal acrylate compounds and oxygen, a patterned ferroelectric layer being formed on the substrate.

US Patent:

8338556, Dec 25, 2012

Filed:

Apr 14, 2011

Appl. No.:

13/064773

Inventors:

Thomas Kirk Dougherty - Playa Del Rey CA, US

Assignee:

The United States of America as Represented by the Secretary of the Navy - Washington DC

International Classification:

G03C 1/00
G03F 7/00
C07C 49/84

US Classification:

526327, 522 44

Abstract:

A patterned composite ferroelectric layer, having ferroelectric electronic properties, on a substrate. Individual layers are each made of metal acrylate compounds, a photoinitiator compound and an acrylate crosslinking compound. The individual layers are stacked on the substrate to form a composite layer. A photomask is formed on the composite layer. Unmasked areas of the composite layer are irradiated with ultraviolet light. A solvent removes non-irradiated areas of the composite layer from the substrate. The patterned composite layer is heated in an oxygen atmosphere to cause a chemical reaction among the metal acrylate compounds and oxygen, a patterned composite ferroelectric layer being formed on the substrate.

US Patent:

20100255312, Oct 7, 2010

Filed:

Nov 17, 2009

Appl. No.:

12/620001

Inventors:

Thomas K. Dougherty - Playa Del Rey CA, US
Christopher T. Snively - McKinney TX, US
Steven E. Lau - Harbor City CA, US
William J. Wolfgong - Little Elm TX, US
Cindy W. Ma - Union City CA, US
Stephen L. Schrader - Murphy TX, US

International Classification:

B32B 27/38
C09D 163/00

US Classification:

428413, 523400, 523457, 523460, 523459, 523456, 523458

Abstract:

The disclosure relates to an X-ray opaque coating containing an epoxy resin including an iodinated phenol covalently bonded to a glycidyl ether. Iodinated phenol covalently bonded to a glycidyl ether may include iodinated bisphenol A, such as tetraiodobisphenol A, a glycidyl ether of mono-iodophenol, bis-iodophenol, tri-iodophenol, or combinations thereof. The coating may include an X-ray opaque inorganic filler. The disclosure also relates to an electronic component including a substrate and at least one device coupled to the substrate with an obfuscation layer disposed over the substrate for obscuring the device from an X-ray source. The obfuscation layer may include an X-ray opaque coating. The disclosure additionally relates to a method of obscuring at least a portion of an electronic component by depositing an obfuscation layer that may include an X-ray opaque coating and a method of forming an X-ray opaque coating.

US Patent:

55759599, Nov 19, 1996

Filed:

Apr 22, 1994

Appl. No.:

8/232897

Inventors:

Norman H. Harris - Newhall CA
Thomas K. Dougherty - Playa Del Rey CA

Assignee:

Hughes Aircraft Company - Los Angeles CA

International Classification:

B29D 1100

US Classification:

264 121

Abstract:

Low cost broadband infrared windows are fabricated using a near net shape process which greatly reduces the cost of machining and grinding window materials. The fabrication of zinc sulfide (ZnS) IR windows uses ceramic powder processing to avoid the expensive prior art chemical vapor deposition method. Further, the invention involves a means of hardening and strengthening ZnS as part of the powder process, with IR transmission performance comparable to undoped CVD-prepared ZnS. The compositional modification used in the practice of the invention involves the introduction of gallium sulfide (Ga. sub. 2 S. sub. 3) as a second phase which acts to toughen and harden the ZnS. The process of the present invention achieves a hardening effect without degrading the IR transmission properties also by means of controlling the polycrystalline microstructure grains to a very small size. At the same time, porosity, which strongly degrades IR transmission, is minimized by full densification. The gallium is introduced into the ZnS by a coprecipitation process to both lower the raw material cost and obtain a suitable submicrometer precursor for the subsequent ceramic processing.

US Patent:

54437466, Aug 22, 1995

Filed:

Feb 14, 1994

Appl. No.:

8/195111

Inventors:

Norman H. Harris - Newhall CA
Brian M. Pierce - Moreno Valley CA
Carl W. Townsend - Los Angeles CA
Thomas K. Dougherty - Playa Del Rey CA

Assignee:

Hughes Aircraft Company - Los Angeles CA

International Classification:

C04B 3546
C04B 4148

US Classification:

252 629

Abstract:

Ferroelectric composites are prepared by sol-gel derived procedures. The present invention utilizes the sol-gel process (1) to form a gel in a mold of the desired size and shape, (2) to dry the gel using a supercritical fluid extraction, (3) to sinter the dried gel to a crystalline ceramic, and finally (4) to impregnate the pores with a low loss polymer. The aerogel composition may be a barium titanate-based composition such as barium strontium titanate (BST). Making a ferroelectric aerogel composite provides a unique and novel means of fully exploiting the voltage- and/or frequency-tunable properties of certain compositions by maximizing their desirable properties and minimizing their undesirable characteristics such as loss at operational frequencies.

US Patent:

49772201, Dec 11, 1990

Filed:

Feb 20, 1990

Appl. No.:

7/485925

Inventors:

Thomas K. Dougherty - Playa del Rey CA
Susan L. Oldham - Torrance CA
William E. Elias - Redondo Beach CA

Assignee:

Hughes Aircraft Company - Los Angeles CA

International Classification:

C08G 5902
C08G 5922
C08C 1906
C08C 1940

US Classification:

5253323

Abstract:

Epoxy end-capped oligomers of 1,3-diolefin compounds of Formula I ##STR1## These oligomers are formed by: (a) reacting a 1,3-diolefin compound having 4 to 12 carbon atoms per molecule with a difunctional initiator comprising anionic reactive sites to form an intermediate living oligomer comprising two anionic end groups; and (b) reacting the intermediate living oligomer with a halohydrin compound to epoxidize the two anionic end groups and form the desired oligomer. The oligomers are subsequently reacted with an epoxidizing agent to form a polymer having epoxy-derived linkages at regular intervals along the chain of the polymer.

US Patent:

56435053, Jul 1, 1997

Filed:

Aug 7, 1995

Appl. No.:

8/511670

Inventors:

Norman H. Harris - Newhall CA
Thomas K. Dougherty - Playa Del Rey CA

Assignee:

Hughes Aircraft Company - Los Angeles CA

International Classification:

B29D 1100
B05B 500
B05D 506

US Classification:

264 121

Abstract:

Low cost broadband infrared windows are fabricated using a near net shape process which greatly reduces the cost of machining and grinding window materials. The fabrication of zinc sulfide (ZnS) IR windows uses ceramic powder processing to avoid the expensive prior art chemical vapor deposition method. Further, the invention involves a means of hardening and strengthening ZnS as part of the powder process, with IR transmission performance comparable to undoped CVD-prepared ZnS. The compositional modification used in the practice of the invention involves the introduction of gallium sulfide (Ga. sub. 2 S. sub. 3) as a second phase which acts to toughen and harden the ZnS. The process of the present invention achieves a hardening effect without degrading the IR transmission properties also by means of controlling the polycrystalline microstructure grains to a very small size. At the same time, porosity, which strongly degrades IR transmission, is minimized by full densification. The gallium is introduced into the ZnS by a coprecipitation process to both lower the raw material cost and obtain a suitable submicrometer precursor for the subsequent ceramic processing.