Cornell Research Foundation Inc.

Bojan (Rob) Ilic

Harold G Craighead

Michal Lipson

Maxim K Zalalutdinov

Robert B Reichenbach

Jeevak M Parpia

Vilson Rosa De Almeida

Keith Aubin

Roberto R Panepucci

David Alan Czaplewski

Robert H Hall

A system and method for detecting mass based on a frequency differential of a resonating micromachined structure, such as a cantilever beam. A high aspect ratio cantilever beam is coated with an immobilized binding partner that couples to a predetermined cell or molecule. A first resonant frequency is determined for the cantilever having the immobilized binding partner. Upon exposure of the cantilever to a solution that binds with the binding partner, the mass of the cantilever beam increases. A second resonant frequency is determined and the differential resonant frequency provides the basis for detecting the target cell or molecule. The cantilever may be driven externally or by ambient noise. The frequency response of the beam can be determined optically using reflected light and two photodetectors or by interference using a single photodetector.

High sensitivity mechanical resonant sensor

Prefabricated catalyzing adsorption sites are incorporated into small oscillators. In one embodiment, the sites are formed of precisely positioned gold anchors on surface micromachined oscillators. The micromachined oscillators may be formed of silicon, such as polysilicon, or silicon nitride in various embodiments. The sites allow special control of chemical surface functionality for the detection of analytes of interest. Thiolate molecules may be adsorbed from solution onto the gold anchors, creating a dense thiol monolayer with a tail end group pointing outwards from the surface of the gold anchor. This results in a thiolate self-assembled monolayer (SAM), creating a strong interaction between the functional group and the gold anchor.

Detection of small bound mass

The temperature of a remote portion of device having a microelectromechanical oscillator is modulated to create oscillation of the oscillators. In one embodiment, a localized heat source is placed on a device layer of a multilayered stack, consisting of device, sacrificial and substrate layers. The localized heat source may be a laser beam in one embodiment. The oscillator is supported by the device layer and may be formed in the device layer in various embodiments. The oscillator may be spaced apart from the localized heat source.

MEMS oscillator drive

A substrate incorporates a mechanical cantilever resonator with passive integrated optics for motion detection. The resonator acts as a waveguide, and enables optical detection of deflection/displacement amplitude, including oscillations. In one embodiment, the cantilever comprises a silicon waveguide suspended over a substrate. A reflector structure faces a free end of the suspending cantilever, or a waveguide is supported facing the free end of the suspended cantilever to receive light transmitted through the silicon waveguide cantilever. Deflection/displacement of the cantilever results in modulation of the light received from its free end that is representative of the displacement. Ring resonators may be used to couple different wavelength light to the waveguides, allowing formation of an array of cantilevers.

Optical waveguide displacement sensor

Growing community of inventors

Ithaca, NY, United States of America

Bojan (Rob) Ilic