Nathan S Newman

US Patent:

6734454, May 11, 2004

Filed:

Aug 26, 2002

Appl. No.:

10/229354

Inventors:

Theodore Van Duzer - El Cerrito CA
Nathan Newman - Scottsdale AZ
Lei Yu - Tempe AZ
Anupama Bhat Kaul - Pasadena CA

Assignee:

The Regents of the University of California - Oakland CA
The Arizona Board of Regents - Tempe AR

International Classification:

H01L 2906

US Classification:

257 31, 257 34, 257 35, 365162, 505162, 505190, 505329

Abstract:

A Josephson junction has inherent resistance which effectively shunts the junction and thereby obviates a separate shunt resistor and thus reduces surface area in an integrated circuit including a plurality of Josephson junctions. The Josephson junction comprises a stacked array of layers of Nb and a superconductor with T 9Â K having a penetration depth greater than that of Nb, for example Nb Ti N, with a layer of a conducting material having a resistivity between 200 -cm, 1 -cm, such as Ta N in the stack. The Josephson junction can be formed on a supporting substrate such as silicon with a ground plane such as Nb on the substrate and an insulating layer such as SiO separating the ground plane from the stacked array.

US Patent:

52078841, May 4, 1993

Filed:

Dec 24, 1990

Appl. No.:

7/633275

Inventors:

Kookrin Char - Palo Alto CA
Nathan Newman - Montara CA
John M. Rowell - Berkeley Heights NJ

Assignee:

Conductus, Inc. - Sunnyvale CA

International Classification:

B05D 306
C23C 1400

US Classification:

20429802

Abstract:

To deposit a plurality of substances on a substrate while the substrate remains in a low pressure oxygen environment, several target carriers are mounted around the edge of a disc and the disc is rotated to position the targets at the focal point of a fixed laser. The target carriers are themselves rotatable in bearings on the disc and are turned by a sun gear that is carried about the same shaft that turns the disc so that the heat of the laser beam is not concentrated at one spot on the surface of the target. All the apparatus is contained in a oxygen chamber. The substrate is heated and the targets are cooled continuously.

US Patent:

52800130, Jan 18, 1994

Filed:

Oct 29, 1992

Appl. No.:

7/968280

Inventors:

Nathan Newman - Montara CA
Aharon Kapitulnik - Palo Alto CA
Brady F. Cole - Sunnyvale CA
Randy W. Simon - Belmont CA

Assignee:

Conductus, Inc. - Sunnyvale CA

International Classification:

H01L 3924

US Classification:

505 1

Abstract:

A superconducting electronic circuit device, useful when impedance matching is desired, especially suited to microwave frequencies, consisting of a thin dielectric layer with superconducting layers on both sides. A superconductor such as Yttrium Barium Copper Oxide (YBCO) is formed on a first substrate such as lanthanum aluminate. A protective layer like gold is deposited on the YBCO and a second carrier substrate is bonded to the protected YBCO. The first substrate is then thinned into a thin dielectric film and a second layer of superconductor is epitaxially grown thereon to create the desired circuits.

US Patent:

56573359, Aug 12, 1997

Filed:

Nov 1, 1993

Appl. No.:

8/146502

Inventors:

Michael Rubin - Berkeley CA
Nathan Newman - Montara CA
Tracy Fu - Berkeley CA
Jennifer Ross - Pleasanton CA
James Chan - Berkeley CA

Assignee:

The Regents, University of California - Oakland CA

International Classification:

H01L 3300

US Classification:

372 44

Abstract:

Several methods have been found to make p-type gallium nitride. P-type gallium nitride has long been sought for electronic devices. N-type gallium nitride is readily available. Discovery of p-type gallium nitride and the methods for making it will enable its use in ultraviolet and blue light-emitting diodes and lasers. pGaN will further enable blue photocathode elements to be made. Molecular beam epitaxy on substrates held at the proper temperatures, assisted by a nitrogen beam of the proper energy produced several types of p-type GaN with hole concentrations of about 5. times. 10. sup. 11 /cm. sup. 3 and hole mobilities of about 500 cm. sup. 2 /V-sec, measured at 250. degree. K. P-type GaN can be formed of unintentionally-doped material or can be doped with magnesium by diffusion, ion implantation, or co-evaporation. When applicable, the nitrogen can be substituted with other group III elements such as Al.

US Patent:

51265338, Jun 30, 1992

Filed:

Mar 19, 1990

Appl. No.:

7/494738

Inventors:

Nathan Newman - Montara CA
Kookrin Char - Palo Alto CA

Assignee:

Conductus, Inc. - Sunnyvale CA

International Classification:

H01L 21203
H05B 318

US Classification:

219385

Abstract:

A substrate heater for the production of superconducting films utilizing a nickel alloy block uniformly heated with a resistance heating element fully immersed in a brazing material that fills a recess in the block. Massive electric power connectors surround the heating element leads outside the braze material so as to provide a protective heat sink therefor and also to mechanically strengthen the block against warpage.

US Patent:

53669533, Nov 22, 1994

Filed:

Dec 22, 1993

Appl. No.:

8/119133

Inventors:

Kookrin Char - Palo Alto CA
Stephen M. Garrison - Palo Alto CA
Nathan Newman - Montara CA
Gregory G. Zaharchuk - Hamilton Square NJ

Assignee:

Conductus, Inc. - Sunnyvale CA

International Classification:

H01L 3922
H01B 1200
B05D 506
B05D 512

US Classification:

505329

Abstract:

A novel method of producing weak-link grain boundary Josephson junctions in high temperature superconducting thin films is disclosed. These junctions are reliably and reproducibly formed on uniform planar substrates (10) by the action of a seed layer (40) placed intermediate the substrate (10) and the superconductor film (20). The superconductor film (22) grown atop the seed (42) is misoriented from the rest of the film (24) by an angle between 5. degree. and 90. degree. The grain boundary (30) so formed acts as a high quality weak-link junction for superconductor devices. The performance of these junctions can be improved by the addition of buffer layers (50, 60) between the substrate (10) and the superconductor film (20).

US Patent:

61372315, Oct 24, 2000

Filed:

Sep 10, 1996

Appl. No.:

8/711844

Inventors:

Andre Anders - Albany CA
Simone Anders - Albany CA
Michael Dickinson - San Leandro CA
Michael Rubin - Berkeley CA
Nathan Newman - Winnetka IL

Assignee:

The Regents of the University of California - Oakland CA

International Classification:

H05H 124

US Classification:

31511121

Abstract:

A constricted glow discharge chamber and method are disclosed. The polarity and geometry of the constricted glow discharge plasma source is set so that the contamination and energy of the ions discharged from the source are minimized. The several sources can be mounted in parallel and in series to provide a sustained ultra low source of ions in a plasma with contamination below practical detection limits. The source is suitable for applying films of nitrides such as gallium nitride and oxides such as tungsten oxide and for enriching other substances in material surfaces such as oxygen and water vapor, which are difficult process as plasma in any known devices and methods. The source can also be used to assist the deposition of films such as metal films by providing low-energy ions such as argon ions.

US Patent:

51574667, Oct 20, 1992

Filed:

Mar 19, 1991

Appl. No.:

7/672664

Inventors:

Kookrin Char - Palo Alto CA
Stephen M. Garrison - Palo Alto CA
Nathan Newman - Montara CA
Gregory G. Zaharchuk - Palo Alto CA

Assignee:

Conductus, Inc. - Sunnyvale CA

International Classification:

H01L 3922
H01B 1200
B05D 512

US Classification:

357 5

Abstract:

Grain boundary, weak-link junctions are formed at a predermined location of a uniform, planar substrate by depositing superconducting film on two sections of the substrate. The film is grown as a bicrystal having two distinct areas of superconducting film whose crystal lattices are rotated with respect to each other, either in-plane or out-of-plane, by more than 5. degree. and less than 90. degree. The grain boundary acts as a weak link junction. The film can be induced to grow as a bicrystal by depositing intermediate strata such as seed layers or buffer layers or by modifying the growth conditions during deposition.