摘要:
A sensor for determining the presence of an analyte is disclosed comprising a reactive layer disposed between a base plate and a movable plate. The reactive layer is configured to interact with an analyte effecting a change in capacitance between the base plate and movable plate. When the analyte has a polarity or overall Hildebrand solubility parameter that is similar to the reactive layer, the change in capacitance is caused by a swelling of the reactive layer as analyte is absorbed into the reactive layer. This results in a decrease in capacitance. When the analyte has a solubility parameter not near the reactive layer, the absorbed analyte causes the reactive layer's total polarity to increase, an effect that dominates swelling. This causes an increase in capacitance. A capacitive sensing circuit is included for measuring the change in capacitance which is indicative of the analyte exposed to the sensor.
摘要:
A sensor for determining the presence of an analyte is disclosed comprising a reactive layer disposed between a base plate and a movable plate. The reactive layer is configured to interact with an analyte effecting a change in capacitance between the base plate and movable plate. When the analyte has a polarity or overall Hildebrand solubility parameter that is similar to the reactive layer, the change in capacitance is caused by a swelling of the reactive layer as analyte is absorbed into the reactive layer. This results in a decrease in capacitance. When the analyte has a solubility parameter not near the reactive layer, the absorbed analyte causes the reactive layer's total polarity to increase, an effect that dominates swelling. This causes an increase in capacitance. A capacitive sensing circuit is included for measuring the change in capacitance which is indicative of the analyte exposed to the sensor.
摘要:
A fixed parallel plate micro-mechanical systems (MEMS) based sensor is fabricated to allow a dissolved dielectric to flow through a porous top plate, coming to rest on a bottom plate. A post-deposition bake ensures further purity and uniformity of the dielectric layer. In one embodiment, the dielectric is a polymer. In one embodiment, a support layer is deposited onto the top plate for strengthening the sensor. In another embodiment, the bottom plate is dual-layered for a narrowed gap. Integrated circuit arrays of such sensors can be made, having multiple devices separated from each other by a physical barrier, such as a polycrystalline containment rim or trough, for preventing polymer material from one sensor from interfering with that of another.
摘要:
A fixed parallel plate micro-mechanical systems (MEMS) based sensor is fabricated to allow a dissolved dielectric to flow through a porous top plate, coming to rest on a bottom plate. A post-deposition bake ensures further purity and uniformity of the dielectric layer. In one embodiment the dielectric is a polymer. In one embodiment, a support layer is deposited onto the top plate for strengthening the sensor. In another embodiment, the bottom plate is dual-layered for a narrowed gap. Integrated circuit arrays of such sensors can be made, having multiple devices separated from each other by a physical barrier, such as a polycrystalline containment rim or trough, for preventing polymer material from one sensor from interfering with that of another.
摘要:
A fixed parallel plate micro-mechanical systems (MEMS) based sensor is fabricated to allow a dissolved dielectric to flow through a porous top plate, coming to rest on a bottom plate. A post-deposition bake ensures further purity and uniformity of the dielectric layer. In one embodiment, the dielectric is a polymer. In one embodiment, a support layer is deposited onto the top plate for strengthening the sensor. In another embodiment, the bottom plate is dual-layered for a narrowed gap. Integrated circuit arrays of such sensors can be made, having multiple devices separated from each other by a physical barrier, such as a polycrystalline containment rim or trough, for preventing polymer material from one sensor from interfering with that of another.
摘要:
Sensors for determining the ambient amount (e.g., concentration) of a chemical (e.g., molecular hydrogen in a gas or vapor) are disclosed. Preferred embodiments of these sensors comprise a dense thin metal (e.g., palladium or a palladium alloy) film disposed on a microcantilever beam that is suspended above a stationary baseplate. The dense thin metal film is configured to absorb, for example, hydrogen, thereby causing the film to expand which in turn causes the microcantilever beam to deform. The deformation can be measured, for example, as a change in capacitance between the microcantilever beam and the stationary baseplate. The measured change in capacitance is indicative of the ambient hydrogen concentration.
摘要:
This method and apparatus for detecting target molecules in a liquid phase. The apparatus monitors whether the target molecule has selectively bound to recognition agents on the surface of a magnetic field sensor by monitoring the output of the sensor. The recognition agents which selectively bind target molecules are covalently bound to microfabricated magnetic field sensors. These sensors are then exposed to a sample suspected of containing the target molecules, whereupon the recognition agents bind to and immobilize any target molecules present. Depending on the embodiment, recognition agents that selectively bind the target molecule, or recognition agents that selectively bind the sensor-bound recognition agents, are covalently bound to magnetizable particles. These particles are then added to the sensors and, again depending on the embodiment, attach either to any immobilized target molecules or to sensor-bound recognition agents. Unattached particles are removed, and the magnetic particles are then magnetized. A change in the output of the magnetic field sensors indicates the presence of magnetic particles bound to the sensors, and thereby indicates the presence and concentration of target molecule in the sample.