Jeffrey F Rhoads

US Patent:

20080110247, May 15, 2008

Filed:

Jun 1, 2007

Appl. No.:

11/809803

Inventors:

Steven W. Shaw - Williamston MI, US
Jeffrey F. Rhoads - Charlotte MI, US
Barry E. DeMartini - Santa Barbara CA, US
Kimberly L. Turner - Santa Barbara CA, US

Assignee:

Board of Trustees of Michigan State University - East Lansing MI

International Classification:

G01N 29/00

US Classification:

73 6453

Abstract:

A sensor is provided which is configured to detect the presence of multiple analytes, for example chemical or biological compounds, through the measurement of induced resonance shifts in a coupled array of microelectromechanical or micromechanical resonators.

US Patent:

20130047710, Feb 28, 2013

Filed:

Aug 27, 2012

Appl. No.:

13/595929

Inventors:

Jeffrey Frederick Rhoads - West Lafayette IN, US
Vjay Kumar - Chennnai, IN

Assignee:

Purdue Research Foundation - West Lafayette IN

International Classification:

G01N 29/02

US Classification:

73 6453

Abstract:

Nonlinear sensors, which actively exploit dynamic transitions across sub-critical or saddlenode bifurcations in the device's frequency response, can exhibit improved performance metrics and operate effectively at smaller scales. This sensing approach directly exploits chemomechanically induced amplitude shifts for detection. Accordingly, it has the potential to eliminate the need for numerous power-consuming signal processing components in final sensor implementations. Various embodiments pertain to low-cost, linear and nonlinear bifurcation-based mass sensors founded upon selectively functionalized, piezoelectrically actuated microcantilevers. Yet other embodiments pertain to an amplitude-based sensing approach based upon dynamic transitions across saddle-node bifurcations that exist in a sensor's nonlinear frequency response.

US Patent:

20140203796, Jul 24, 2014

Filed:

Aug 16, 2013

Appl. No.:

13/968836

Inventors:

- West Lafayette IN, US
Hossein Pajouhi - West Lafayette IN, US
Jeffrey Frederick Rhoads - West Lafayette IN, US
Lin Yu - San Jose CA, US

Assignee:

Purdue Research Foundation - West Lafayette IN

International Classification:

H01L 27/12
G01R 19/00
H01L 29/02

US Classification:

324 7611, 257351, 257632

Abstract:

A silicon device, e.g., a nanoelectromechanical resonator, has a silicon substrate; an oxide layer having a trench therein; a silicon device layer over the oxide layer; and a nanowire disposed at least partly over the trench. Substantially no oxide or polysilicon is over the nanowire in the trench. A polyimide layer over the silicon device layer includes an opening over the trench. A silicon device can include silicon-on-insulator layers and at least one complementary metal-oxide semiconductor transistor in addition to a nanowire substantially suspended over a trench. A system for measurement of a nanoresonator includes an AC source in series with the nanoresonator to provide an electrical signal thereto at a selected first frequency. Electrode(s) adjacent to and spaced apart from the nanoresonator are driven by voltage source. A detector detects a current through the nanoresonator.