Gang Liu

US Patent:

7948042, May 24, 2011

Filed:

Mar 3, 2009

Appl. No.:

12/397183

Inventors:

Chun Ning Lau - Diamond Bar CA, US
Gang Liu - Riverside CA, US
Jairo Velasco, Jr. - Riverside CA, US

Assignee:

The Regents of the University of California - Oakland CA

International Classification:

H01L 29/84

US Classification:

257415, 257417, 257419, 257E43002, 257E43003, 257E43007, 257E27005, 257E27046, 257E27064

Abstract:

A multi-level lithography processes for the fabrication of suspended structures are presented. The process is based on the differential exposure and developing conditions of several a plurality of resist layers, without harsher processes, such as etching of sacrificial layers or the use of hardmasks. These manufacturing processes are readily suited for use with systems that are chemically and/or mechanically sensitive, such as graphene. Graphene p-n-p junctions with suspended top gates formed through these processes exhibit high mobility and control of local doping density and type. This fabrication technique may be further extended to fabricate other types of suspended structures, such as local current carrying wires for inducing local magnetic fields, a point contact for local injection of current, and moving parts in microelectromechanical devices.

US Patent:

8170844, May 1, 2012

Filed:

May 2, 2008

Appl. No.:

12/151119

Inventors:

Robert J. Buchler - Calabasas CA, US
Gang Kevin Liu - Simi Valley CA, US

Assignee:

Northrop Grumman Guidance and Electronics Company, Inc. - Woodland Hills CA

International Classification:

G06F 7/60
G01C 21/00

US Classification:

703 2, 701213

Abstract:

A method for estimating a probability of failure of a least-squares ambiguity decorrelation adjustment (LAMBDA) method is provided. The LAMBDA method is used for estimation of double difference carrier phase integer ambiguity. A plurality of condition sets are selected. Each condition set comprises a probability of failure (P) for a boot-strap method of estimation of the double difference carrier phase integer ambiguity, a number of space vehicles (N), and a ratio test tolerance for the LAMBDA method. A plurality of Monte Carlo simulations are run on the plurality of condition sets to obtain a plurality of result sets. Each result set comprises a probability of lambda fail (P) and a probability of lambda reject (P) for one condition set of the plurality of condition sets. A lookup table is created with the plurality of result sets. A value of Pfor given values of P, P, and Nis estimated through employment of the lookup table.