University of Michigan

Ford Motor Company Limited

University of California

Carlos H Mastrangelo

Mark A Burns

James R Webster

Brian N Johnson

David T Burke

Francis P Man

Darren Jones

Bradley Foerster

Timothy S Sammarco

Richard S Muller

Yakeitha Fields

Adam Kaiser

Kalyan Handique

Bishnu Prasanna Gogoi

Piu Francis Man

Edwin Thomas Carlen

Ponnambalam Selvaganapathy

Chien-Chang Liu

Kirt R Williams

The present invention relates to microfabrication and utilization of microscale electrophoresis devices as well as the separation and detection of biomolecules in microscale electrophoresis devices. The device of the present invention utilizes novel fabrication and detection methods.

Microscale electrophoresis devices for biomolecule separation and detection

The movement and mixing of microdroplets through microchannels is described employing silicon-based microscale devices, comprising microdroplet transport channels, reaction regions, electrophoresis modules, and radiation detectors. The discrete droplets are differentially heated and propelled through etched channels. Electronic components are fabricated on the same substrate material, allowing sensors and controlling circuitry to be incorporated in the same device.

Microscale reaction devices

A microfluidic device adapted for use with a power source is disclosed. The device includes a substrate and a heater member. The substrate and heater member form a first portion. A second portion is formed adjacent to the first portion. The second portion includes a high activating power polymer portion, at least one resin layer and a shield member. The second portion is selectively shaped to form a thermal expansion portion. A diaphragm member encapsulates the thermal expansion portion so that when power is applied to the heater portion, the high activating power polymer expands against the diaphragm member, causing the diaphragm member to deflect. This device is adapted for use as a microactuator or a blocking microvalve.

Thermally activated polymer device

An uncooled infrared imager and associated microelectromechanical infrared detectors based on an active pixel heat balancing technique are disclosed. The imager is fabricated using a commercial CMOS process plus a simple electrochemical etch stop releasing step. The basic active pixel detector structure consists of a simple cascode CMOS amplifier in which the PMOS devices are built inside a thermally-isolated floating n-well. The intrinsic coupling of the cascode currents with the self-heating of the well forms an electrothermal feedback loop that tends to maintain the well temperature constant. By employing the heat balance between incoming infrared radiation and the PMOS device power dissipation, the responsivity of the detector is controlled by the cascode biasing current.

Uncooled infrared focal plane imager and microelectromechanical infrared detector for use therein

Microscale devices and reactions in microscale devices

The present invention relates to polymer-based micro-electro-mechanical system (MEMS) technology suitable for the fabrication of integrated microfluidic systems, particularly medical and chemical diagnostics system, ink-jet printer head, as well as any devices that requires liquid- or gas-filled cavities for operation. The integrated microfluidic systems may consist of pumps, valves, channels, reservoirs cavities, reaction chambers, mixers, heaters, fluidic interconnects, diffusers, nozzles, and other microfluidic components on top of a regular circuit substrate. This technology is vastly superior than any alternatives available such as glass-based, polysilicon-based MEMS technology as well as hybrid `circuit board` technology because of its simple construction low cost, low temperature processing, and its ability to integrate any electronic circuitry easily along with the fluidic parts.

Polymer-based micromachining for microfluidic devices

The movement and mixing of microdroplets through microchannels is described employing microscale devices, comprising microdroplet transport channels, reaction regions, electrophoresis modules, and radiation detectors. The discrete droplets are differentially heated and propelled through etched channels. Electronic components are fabricated on the same substrate material, allowing sensors and controlling circuitry to be incorporated in the same device.

Moving microdroplets

A surface and/or bulk micromachined hermetically sealed cavity containing at least one suspended structure in a low pressure ambient, and the associated fabrication method. The cavity is bounded by a thin-film membrane and a substrate which may have a recess. The method can be used for the production, for example, of thermionic-emission vacuum tubes, gas filled tubes and electromechanical devices. In vacuum tubes the cathode is a suspended refractory filament. Other electrodes may also be suspended. In electromechanical devices the suspended members may be cantilever beams capable of low friction motion.

Sealed micromachined vacuum and gas filled devices

A method and structure for forming a capacitive transducer having a deformable single crystal diaphragm. A first well region is formed within a semiconductor substrate in an SOI wafer having a sacrificial layer of known thickness and a top single-crystal silicon layer thereon. Next, a silicon, epitaxial layer is deposited on the top silicon layer for forming a flexible single crystal membrane. The epitaxial layer and the sacrificial layer are masked and etched to define the flexible diaphragm. An electrical insulating conformal support layer is deposited on the substrate and attached to the diaphragm so as to seal the sacrificial layer therebetween. An access opening is etched through the diaphragm, and then a wet etchant is inserted through the access opening for removing the sacrificial layer, thereby defining a diaphragm cavity between the remaining epitaxial layer and the substrate. Conductive ions are diffused into facing sections of the diaphragm and the first well of the substrate so as to define fixed and deformable electrodes of the sensing capacitor. Next, a plug is selectively deposited within and for sealing the access opening without substantially reducing the volume of the diaphragm cavity.

Method for producing a silicon-on-insulator capacitive surface

A method and structure for forming a capacitive transducer having a deformable single crystal diaphragm. A first well region is formed within a semiconductor substrate in an SOI wafer having a sacrificial layer of known thickness and a top single-crystal silicon layer thereon. Next, a silicon epitaxial layer is deposited on the top silicon layer for forming a flexible single crystal membrane. The epitaxial layer and the sacrificial layer are masked and etched to define the flexible diaphragm. An electrical insulating conformal support layer is deposited on the substrate and attached to the diaphragm so as to seal the sacrificial layer therebetween. An access opening is etched through the diaphragm, and then a wet etchant is inserted through the access opening for removing the sacrificial layer, thereby defining a diaphragm cavity between the remaining epitaxial layer and the substrate. The thickness of the diaphragm cavity is substantially equal to the thickness of the sacrificial layer removed from the SOI wafer. Conductive ions are diffused into facing sections of the diaphragm and the first well of the substrate so as to define fixed and deformable electrodes of the sensing capacitor. Next, a plug is selectively deposited within and for sealing the access opening without substantially reducing the volume of the diaphragm cavity. In this manner, a deflection of the flexible diaphragm in response to variations between the ambient pressure and the pressure sealed within the diaphragm cavity causes a o corresponding change in the capacitance between the first well region and the conductive region in the diaphragm. A reference capacitive sensor of similar construction is also provided for ratiometric pressure measurements. A pressure transducer manufactured in accordance with this process is also described.

Silicon-on-insulator capacitive surface micromachined absolute pressure

A surface layer and a sacrificial layer are deposited on a substrate. A conductive structural layer bridges over the sacrificial layer and is anchored to the surface layer for creating paired conductive areas. A backside opening is etched in the substrate for defining a flexible diaphragm layer of reduced thickness. The sacrificial layer is removed so that pressures exerted on the backside opening will cause a change in capacitance between the paired conductive areas. Temporary posts support the conductive structural layer as the sacrificial layer is removed.

Capacitive surface micromachined differential pressure sensor

A polysilicon diaphragm is formed on top of a sacrificial layer deposited upon a semiconductor substrate, where the thickness of the layer is controllable. The sacrificial layer is removed to define a diaphragm cavity, which is sealed with a plug. Electrodes within the surfaces defining the cavity deflect in response to variations in pressure, while providing a very small and minimum parasitic capacitance.

Capacitive surface micromachine absolute pressure sensor and method for

A microlamp including a polysilicon filament coated with a protective layer and enclosed by a window in a vacuum-sealed cavity.

Vacuum-sealed silicon incandescent light

A dry-release method for sacrificial layer microstructure fabrication is provided in which a structural layer is anchored to a substrate and deposited on a sacrificial layer located therebetween. Thereafter, holes are etched through the structural layer. Some of the holes are covered with a polymer layer, and portions of the sacrificial layer are then etched through the uncovered holes in the structural layer, creating void areas extending to the substrate. Preferably, the void areas also include undercut areas. The void areas are then filled with a protective polymer layer, creating temporary posts that extend from the surface of the substrate to the structural layer. The sacrificial layer is then removed by means of wet etching. The temporary posts provide support for the structural layer against capillary forces which are created by the evaporation of liquids used in the wet etching process. After wet etching of the sacrificial layer is completed, the temporary posts are removed by a dry etching technique. The resulting microstructure consists of a free-standing structural layer that is anchored to the substrate.

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Ann Arbor, MI, United States of America

Carlos H Mastrangelo