Richard A Greene

US Patent:

48430609, Jun 27, 1989

Filed:

Nov 23, 1987

Appl. No.:

7/123629

Inventors:

Howard Lessoff - Potomac MD
Richard F. Greene - Bethesda MD

Assignee:

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

International Classification:

B05D 512

US Classification:

505 1

Abstract:

A method for growing a patterned superconductive oxide film of the general formula XZ. sub. 2 Cu. sub. 3 O. sub. 6+x is disclosed, wherein X is yttrium, a lanthanide or a mixture thereof, Z is one or more alkaline earth elements and x is a number between 0 and 1. This patterned superconductive oxide film of XZ. sub. 2 Cu. sub. 3 O. sub. 6+x is formed by preparing an aqueous solutuion of the nitrates of X, Z and Cu in the X:Z:Cu stoichiometric ratio of 1:2:3; spraying the aqueous nitrate solution onto a heated substrate to form on the substrate a thin film of XZ. sub. 2 Cu. sub. 3 O. sub. y material, wherein y is an undefined number; spot-heating preselected portions of the thin film in an oxygen-rich atmosphere to convert the preselected portions into the patterned superconductive oxide film of XZ. sub. 2 Cu. sub. 3 O. sub. 6+x ; and removing the unheated thin film of XZ. sub. 2 Cu. sub. 3 O. sub. y material with a solvent.

US Patent:

43718094, Feb 1, 1983

Filed:

Jun 19, 1980

Appl. No.:

6/161183

Inventors:

Richard E. Thomas - Riverdale MD
George A. Haas - Alexandria VA
Richard F. Greene - Bethesda MD

Assignee:

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

International Classification:

H01J 2946
H01J 1942

US Classification:

313449

Abstract:

In a controlled-porosity dispenser cathode of the type which has a foil w a plurality of holes covering the emitting material so that emitting material is dispensed through the holes to the electron-emitting surface of the foil and electrons are actually emitted through the holes and a small area surrounding each hole, a non-emitting shadow grid is laid down on the surface of the foil in such a configuration that it does not obstruct any of the emitting holes, has the same shape as the control grid, and is substantially in precise registration with the control grid.

US Patent:

45133085, Apr 23, 1985

Filed:

Sep 23, 1982

Appl. No.:

6/421766

Inventors:

Richard F. Greene - Bethesda MD
Henry F. Gray - Alexandria VA

Assignee:

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

International Classification:

H01L 2906
H01L 2934
H01L 2712

US Classification:

357 55

Abstract:

A Field Emitter Array comprising a semiconductor substrate with an emitter urface formed thereon. A plurality of emitter pyramids is disposed on the emitter surface for emitting an electron current. The magnitude of the electron current emitted by each emitter pyramid I. sub. max, is controlled by a reverse-biased p-n junction associated with each emitter pyramid where I. sub. max =j. sub. sat X A. sub. p-n, j. sub. sat being the saturation current density and A. sub. p-n being the area of the reverse-biased p-n junction associated with each emitter pyramid. A grid, positively biased relative to the emitter surface and the emitter pyramids, is disposed above the emitter surface for creating an electric field that induces the emission of the electron current from the emitter tips.

US Patent:

41475151, Apr 3, 1979

Filed:

Dec 22, 1977

Appl. No.:

5/863363

Inventors:

George A. Haas - Alexandria VA
Richard F. Greene - Bethesda MD
Arnold Shih - Gaithersburg MD

Assignee:

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

International Classification:

G01N 2704

US Classification:

23232E

Abstract:

An electro-chemical gas sensor for use in electron tubes comprising a crylline body of BaO formed on a non-interacting (chemically and electrically) substrate and at least two electrodes. The change in conductivity of the barium oxide upon exposure to tube gases may be used to determine the type and quantity of gases contaminating the electron emitter and estimate changes in the emitter's work function or electron emission capability due to gas contamination.

US Patent:

43799795, Apr 12, 1983

Filed:

Feb 6, 1981

Appl. No.:

6/232444

Inventors:

Richard E. Thomas - Riverdale MD
Richard F. Greene - Bethesda MD

Assignee:

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

International Classification:

H01J 114
H01J 1906
H01K 104

US Classification:

313346R

Abstract:

A controlled porosity sheet defining a surface for a thermionic dispenser thode and a method of manufacture. Starting with a generally flat silicon template substrate structure having an array of upstanding microposts 1-25 microns across on 5-100 micron spacings from each other, a layer of metal is deposited on the substrate to surround the microposts and cover the substrate structure to a desired depth. The metal layer is then abraded to a smooth, flat surface which exposes the microposts. Thereafter, the silicon substrate and microposts are completely etched away, leaving a metal sheet having micron-size holes therethrough.

US Patent:

45786143, Mar 25, 1986

Filed:

Jul 23, 1982

Appl. No.:

6/401277

Inventors:

Henry F. Gray - Alexandria VA
Richard F. Greene - Bethesda MD

Assignee:

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

International Classification:

H01J 102

US Classification:

313309

Abstract:

A field-emitter switching device wherein a positive pulse is applied to a te (which is held at a bias potential V. sub. 1 just below turn-on). A collector is held at a potential higher than the gate in order to collect emitted electrons from a field emitter source. As the voltage is applied to the gate, electrons are emitted immediately from the source and travel to the most positive potential at the collector. Because of the field emitter geometry, such electron transport is extremely fast. The ultra-fast switching speed is attained because the electrons reach near-maximum velocity within a few field tip diameters of the source.

US Patent:

49010280, Feb 13, 1990

Filed:

Mar 22, 1988

Appl. No.:

7/171706

Inventors:

Henry F. Gray - Alexandria VA
Richard F. Greene - Bethesda MD

Assignee:

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

International Classification:

H03F 360

US Classification:

330 54

Abstract:

Distributed amplifiers in integrated circuit form wherein dielectric material and electrically conductive material combine to form field emitter cathodes, grids, and anodes in a module forming one or more amplifier cells embedded in a matrix of reactive impedances that form companion stripline-like transmission lines in a vacuum or sufficiently low pressure gas such that electrons remain unscattered during travel over trajectories from cathode to anode in a cell.

US Patent:

43075070, Dec 29, 1981

Filed:

Sep 10, 1980

Appl. No.:

6/185702

Inventors:

Henry F. Gray - Alexandria VA
Richard F. Greene - Bethesda MD

Assignee:

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

International Classification:

B01J 1700
H01J 102

US Classification:

29580

Abstract:

A method of manufacturing a field-emitter array cathode structure in which substrate of single crystal material is selectively masked such that the unmasked areas define islands on the underlying substrate. The single crystal material under the unmasked areas is orientation-dependent etched to form an array of holes whose sides intersect at a crystallographically sharp point. Following removal of the mask, the substrate is covered with a thick layer of material capable of emitting electrons which extends above the substrate surface and fills the holes. Thereafter, the material of the substrate underneath the layer of electron-emitting material is etched to expose a plurality of sharp field-emitter tips.