Abstract: According to some embodiments, an electronics based physical gas sensor includes a semiconductor layer, and at least one contact is electrically coupled to the semiconductor layer. A catalytic gate, having a property that changes when the gate is exposed to an analyte, and a variable bias from a voltage source are also provided.

Abstract: According to some embodiments, an electronics based physical gas sensor includes a semiconductor layer, and at least one contact is electrically coupled to the semiconductor layer. A catalytic gate, having a property that changes when the gate is exposed to an analyte, and a variable bias from a voltage source are also provided.

Abstract: A device including a first layer having a first material, and the first material having a hexagonal crystal lattice structure defining a first bandgap and one or more non-polar planes is provided. The device further includes a second layer that is adjacent to the first layer having a second material. The second material may have a second bandgap that is different than the first bandgap. The second layer may have a first surface and a second surface, and a portion of the second layer first surface may be coupled to a surface of the first layer to form a two dimensional charge gas and to define a first region. Further, the device includes a conductive layer that is interposed between the first region and a second region that is spaced from the first region, where the device is normally-off if no electrical potential is applied to the conductive layer, and an electrical potential applied to the conductive layer allows electrical communication from the first region to the second region.

Abstract: A multi-gas sensor device for the detection of dissolved hydrocarbon gases in oil-filled electrical equipment. The device comprising a semiconductor substrate, one or more catalytic metal gate-electrodes deposited on the surface of the semiconductor substrate operable for sensing various gases, and an ohmic contact deposited on the surface of the semiconductor substrate. The semiconductor substrate comprises one of GaN, SiC, AlN, InN, AlGaN, InGaN and AlInGaN. A method for sensing gas in an oil-filled reservoir of electrical equipment, comprising providing a sensor device, immersing the sensor device in the oil-filled reservoir, allowing the gases emitted from the oil to interact with the one or more catalytic metal gate-electrodes, altering the gas as it contacts the catalytic metal gate-electrodes and altering the sensitivity of the sensor.

Abstract: A vertical heterostructure field effect transistor including a first layer having a first material, and the first material having a hexagonal crystal lattice structure defining a first bandgap and one or more non-polar planes is provided. The transistor further includes a second layer that is adjacent to the first layer having a second material. Further, the second layer has a first surface and a second surface, and a portion of the second layer first surface is coupled to the surface of the first layer to form a two dimensional charge gas and to define a first region. The second material may have a second bandgap that is different than the first bandgap.

Abstract: A sensor, in accordance with aspects of the present technique, is provided. The sensor comprises a membrane formed of gallium nitride. The membrane is disposed on a substrate, which is wet-etched to form a closed cavity. The membrane exhibits both a capacitive response and a piezo-response to an external stimulus. The sensor further includes a circuit for measuring at least one of the capacitive response or the piezo-response. In certain aspects, the sensor may be operable to measure external stimuli, such as, pressure, force and mechanical vibration.

Abstract: A pressure sensor is provided. The pressure sensor includes a multi-layer laminate comprising a substrate and a semiconductor layer, wherein the substrate comprises single crystal or quasi-single crystal aluminum oxide, and a portion of the substrate that is spaced from a peripheral edge is wet etched to form an inwardly facing sidewall that defines a volume; and a substrate to which the multi-layer laminate is secured. The volume is an enclosed volume further defined by a substrate surface.

Abstract: An etchant including a halogenated salt, such as Cryolite (Na3AlF6) or potassium tetrafluoro borate (KBF4), is provided. The salt may be present in the etchant in an amount sufficient to etch a substrate and may have a melt temperature of greater than about 200 degrees Celsius. A method of wet etching may include contacting an etchant to at least one surface of a support layer of a multi-layer laminate, wherein the support layer may include aluminum oxide; or contacting an etchant to at least one surface of a support layer of a multi-layer laminate, wherein the etchant may include Cryolite (Na3AlF6), potassium tetrafluoro borate (KBF4), or both; and etching at least a portion of the support layer. The method may provide a laminate produced by growing a crystal onto an aluminum oxide support layer, and chemically removing at least a portion of the support layer by wet etch. An electronic device, optical device or combined device including the laminate is provided.

Abstract: A high-temperature pressure sensor that includes a dielectric layer. The pressure sensor also includes a substrate capable of withstanding temperatures greater than 450° C. without entering a phase change, at least one semiconducting material deposited on the sapphire substrate, and a silicon dioxide layer deposited over the semiconducting material. One aspect of the pressure sensor includes a second semiconducting material.

Abstract: According to some embodiments, an electronics based physical gas sensor includes a semiconductor layer, and at least one contact is electrically coupled to the semiconductor layer. A catalytic gate, having a property that changes when the gate is exposed to an analyte, and a variable bias from a voltage source are also provided.

Abstract: A sensor, in accordance with aspects of the present technique, is provided. The sensor comprises a membrane formed of gallium nitride. The membrane is disposed on a substrate, which is wet-etched to form a closed cavity. The membrane exhibits both a capacitive response and a piezo-response to an external stimulus. The sensor further includes a circuit for measuring at least one of the capacitive response or the piezo-response. In certain aspects, the sensor may be operable to measure external stimuli, such as, pressure, force and mechanical vibration.

Abstract: A gas sensor device including a semiconductor substrate; one or more catalytic gate-electrodes deposited on a surface of the semiconductor substrate; one or more ohmic contacts deposited on the surface of the semiconductor substrate and a passivation layer deposited on at least a portion of the surface; wherein the semiconductor substrate includes a material selected from the group consisting of silicon carbide, diamond, Group III nitrides, alloys of Group III nitrides, zinc oxide, and any combinations thereof.

Abstract: A gas sensor device including a semiconductor substrate; one or more catalytic gate-electrodes deposited on a surface of the semiconductor substrate; one or more ohmic contacts deposited on the surface of the semiconductor substrate and a passivation layer deposited on at least a portion of the surface; wherein the semiconductor substrate includes a material selected from the group consisting of silicon carbide, diamond, Group III nitrides, alloys of Group III nitrides, zinc oxide, and any combinations thereof.

Abstract: A multi-gas sensor device for the detection of dissolved hydrocarbon gases in oil-filled electrical equipment. The device comprising a semiconductor substrate, one or more catalytic metal gate-electrodes deposited on the surface of the semiconductor substrate operable for sensing various gases, and an ohmic contact deposited on the surface of the semiconductor substrate. The semiconductor substrate comprises one of GaN, SiC, AlN, InN, AlGaN, InGaN and AlInGaN. A method for sensing gas in an oil-filled reservoir of electrical equipment, comprising providing a sensor device, immersing the sensor device in the oil-filled reservoir, allowing the gases emitted from the oil to interact with the one or more catalytic metal gate-electrodes, altering the gas as it contacts the catalytic metal gate-electrodes and altering the sensitivity of the sensor.