University of Louisville Research Foundation

Other

United States of America as Represented by the Secretary of the Air Force

Picocal, Inc

Shamus Patrick McNamara

Joseph Devin Schneider

Yogesh B Gianchandani

John G Jones

Frank K Hopkins

Pranoy Deb Shuvra

Kunal Pharas

In accordance with various embodiments of the disclosed subject matter, a phototransistor comprises an NPN or PNP phototransistor having a base including a Si-region, a Ge-region, and a Ge&#x2014;Si interface region wherein photons are absorbed in the Ge region and conduction-band electrons are attracted to the interface region such that the electrons' mobility is enhanced thereby.

Si&#x2014;Ge&#x2014;Si phototransistor

A strained bilayer film with reinforcing members is used to open and close gas flow outlets in a microvalve array. The bottom layer of the bilayer film is compressive and the top layer is tensile. Reinforcing members are made from compressive material that accomplishes the dual objectives of reducing potential defects at the interface between the anchor region and the free region of the actuator, and controlling the stresses along the edges of the strained bilayer to avoid curling as the actuator unrolls from its normal coiled configuration in response to an applied voltage. Because of the configuration, the strained bilayer film occupies a minimal amount of space compared to other systems when the valve is opened, and it permits a higher density of microvalves to be utilized. Optional supports are provided over gas flow channel openings to increase the area over which the voltage is applied, increasing electrostatic stability of the actuators in maintaining their unrolled state for a variety of uses. Such uses include, but are not limited to, pneumatic manifolds or other practical uses that involve transmission of air or fluids, including for lab-on-a-chip applications, as well as for providing air flow channels for a configurable tactile tablet to provide the visually impaired with a tactile representation of shapes and designs, to name some examples.

Bilayer microvalve arrays for pneumatic and fluidic applications

Energy storage devices are disclosed that store both electrical and mechanical energies, making the total energy stored larger than either an electrical or mechanical means alone. The energy storage device is charged by the application of a voltage, which charges a capacitor to store electrical energy while simultaneously exerting a force on the mechanical system that deforms the mechanical system, resulting in mechanical energy storage. When the charged device is discharged, both the electrical and mechanical energy are extracted in electrical form. Its unique features include, but are not limited to, the potential for long lifetime, improved safety, better portability, a wide operating temperature range, and environment friendliness. Arrays of energy storage devices can be assembled in various configurations to build high capacity energy storage units.

Strain capacitor energy storage devices and assemblies

The present invention relates to thermally driven pumps. More specifically, one embodiment of the present invention relates to the use of a thermoelectric material to create a thermally driven, bi-directional pump, such as a micro pump, with no moving parts using the thermal transpiration effect (a Knudsen pump). One embodiment of the thermally driven pump of the present invention utilizes a thermoelectric material to assist with the thermal transpiration process resulting in a substantially symmetrical, bidirectional pump. A thermoelectric module is used to induce a temperature gradient across a nanoporous article having at least one nanochannel thus creating fluid flow via thermal transpiration across the nanochannel. The use of the thermoelectric module eliminates the need for a heat sink thereby making the pump substantially symmetrical and enabling bidirectional flow which is accomplished by reversing the polarity of the power supply to the thermoelectric module resulting in reversing the direction of heat transfer. A second embodiment of the thermally driven pump of the present invention comprises a uni-directional, pneumatic, micro fluidic, Knudsen pump which can be integrated into a lab-on-chip device and is configured to pump liquids. The Knudsen pump of the second embodiment is generally comprised of a channel system comprised of a nanochannel and a shallow channel embedded in a bottom substrate and capable of alignment in series with other channels within a lab-on-chip substrate. The nanochannel and shallow channel are both covered by a second substrate comprised of material conducive to finalize creation of the Knudsen channels. A heater is also included within the nanochannel to induce gas flow by thermal transpiration which pneumatically moves liquid through the channels of a lab-on-chip.

Thermally driven Knudsen pump

Systems and methods are described for identifying characteristics and defects in material such as semiconductors. Methods include scanning a thermal probe in the vicinity of a semiconductor sample, applying stimuli to the thermal probe, and monitoring the interaction of the thermal probe and the semiconductor. The stimulus can be applied by a variety of methods, including Joule heating of a resistor in the proximity of the probe tip, or optically heating a tip of the thermal probe using a laser. Applications of the invention include identification of voids in metallic layers in semiconductors; mapping dopant concentration in semiconductors; measuring thickness of a sample material; mapping thermal hot spots and other characteristics of a sample material.

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New Salisbury, IN, United States of America

Shamus Patrick McNamara