Abstract:
The present disclosure is directed to a gas sensor that includes an active sensor area that is exposed to an environment for detection of elements. The gas sensor may be an air quality sensor that can be fixed in position or carried by a user. The gas sensor includes a heater formed above chamber. The gas sensor includes an active sensor layer above the heater that forms the active sensor area. The gas sensor can include a passive conductive layer, such as a hotplate that further conducts and distributes heat from the heater to the active sensor area. The heater can include a plurality of extensions. The heater can also include a first conductive layer and a second conductive layer on the first conductive layer where the second conductive layer includes a plurality of openings to increase an amount of heat and to more evenly distribute heat from the heater to the active sensor area.
Abstract:
A universal electrochemical micro-sensor can be used either as a biosensor or an environmental sensor. Because of its small size and flexibility, the micro-sensor is suitable for continuous use to monitor fluids within a live subject, or as an environmental monitor. The micro-sensor can be formed on a reusable glass carrier substrate. A flexible polymer backing, together with a set of electrodes, forms a reservoir that contains an electrolytic fluid chemical reagent. During fabrication, the glass carrier substrate protects the fluid chemical reagent from degradation. A conductive micromesh further contains the reagent while allowing partial exposure to the ambient biological or atmospheric environment. The micromesh density can be altered to accommodate fluid reagents having different viscosities. Flexibility is achieved by attaching a thick polymer tape and peeling away the micro-sensor from the glass carrier substrate. The final structure is thereby transferred to the polymer tape, providing a flexible product.
Abstract:
The present disclosure is directed to a gas sensor device that includes a plurality of gas sensors. Each of the gas sensors includes a semiconductor metal oxide (SMO) film, a heater, and a temperature sensor. Each of the SMO films is designed to be sensitive to a different gas concentration range. As a result, the gas sensor device is able to obtain accurate readings for a wide range of gas concentration levels. In addition, the gas sensors are selectively activated and deactivated based on a current gas concentration detected by the gas sensor device. Thus, the gas sensor device is able to conserve power as gas sensors are on when appropriate instead of being continuously on.
Abstract:
A microelectronic device capable of detecting multiple gas constituents in ambient air can be used to monitor air quality. The microelectronic air quality monitor includes a plurality of temperature-sensitive gas sensors tuned to detect different gas species. Each gas sensor is tuned by programming an adjacent heater. An insulating air pocket formed below the sensor helps to maintain the sensor at a desired temperature. A temperature sensor may also be integrated with each gas sensor to provide additional feedback control. The heater, temperature sensor, and gas sensors are in the form of patternable thin films integrated on a single microchip. The device can be incorporated into computer workstations, smart phones, clothing, or other wearable accessories to function as a personal air quality monitor that is smaller, more accurate, and less expensive than existing air quality sensors.
Abstract:
A miniature gas analyzer capable of detecting VOC gases in ambient air as well as sensing relative humidity and ambient temperature can be used to monitor indoor air quality. The VOC gas sensor is thermally controlled and can be tuned to detect a certain gas by programming an adjacent heater. An insulating air pocket formed below the sensor helps to maintain the VOC gas sensor at a desired temperature. A local temperature sensor may be integrated with each gas sensor to provide feedback control. The heater, local temperature sensor, gas sensor(s), relative humidity sensor, and ambient temperature sensor are in the form of patternable thin films integrated on a single microchip, e.g., an ASIC. The device can be incorporated into computer workstations, smart phones, clothing, or other wearable accessories to function as a personal air quality monitor that is smaller, more accurate, and less expensive than existing air quality sensors.
Abstract:
A semiconductor-based multi-sensor module integrates miniature temperature, pressure, and humidity sensors onto a single substrate. Pressure and humidity sensors can be implemented as capacitive thin film sensors, while the temperature sensor is implemented as a precision miniature Wheatstone bridge. Such multi-sensor modules can be used as building blocks in application-specific integrated circuits (ASICs). Furthermore, the multi-sensor module can be built on top of existing circuitry that can be used to process signals from the sensors. An integrated multi-sensor module that uses differential sensors can measure a variety of localized ambient environmental conditions substantially simultaneously, and with a high level of precision. The multi-sensor module also features an integrated heater that can be used to calibrate or to adjust the sensors, either automatically or as needed. Such a miniature integrated multi-sensor module that features low power consumption can be used in medical monitoring and mobile computing, including smart phone applications.
Abstract:
A semiconductor-based multi-sensor module integrates miniature temperature, pressure, and humidity sensors onto a single substrate. Pressure and humidity sensors can be implemented as capacitive thin film sensors, while the temperature sensor is implemented as a precision miniature Wheatstone bridge. Such multi-sensor modules can be used as building blocks in application-specific integrated circuits (ASICs). Furthermore, the multi-sensor module can be built on top of existing circuitry that can be used to process signals from the sensors. An integrated multi-sensor module that uses differential sensors can measure a variety of localized ambient environmental conditions substantially simultaneously, and with a high level of precision. The multi-sensor module also features an integrated heater that can be used to calibrate or to adjust the sensors, either automatically or as needed. Such a miniature integrated multi-sensor module that features low power consumption can be used in medical monitoring and mobile computing, including smart phone applications.
Abstract:
A micro-sensor device that includes a passivation-protected ASIC module and a micro-sensor module bonded to a patterned cap provides protection for signal conditioning circuitry while allowing one or more sensing elements in the micro-sensor module to be exposed to an ambient environment. According to a method of fabricating the micro-sensor device, the patterned cap can be bonded to the micro-sensor module using a planarizing adhesive that is chemically compatible with the sensing elements. In one embodiment, the adhesive material is the same material used for the dielectric active elements, for example, a photo-sensitive polyimide film.
Abstract:
A bio-fluid sensor is formed by depositing polyimide on a glass substrate. Gold and platinum are deposited on the polyimide and patterned to form fluid sensing electrodes, signal traces, and a temperature sensor. The fluid sensor is then fixed to a flexible tape and peeled off of the glass substrate.
Abstract:
An integrated circuit is formed having an array of memory cells located in the dielectric stack above a semiconductor substrate. Each memory cell has two adjustable resistors and two heating elements. A dielectric material separates the heating elements from the adjustable resistors. One heating element alters the resistance of one of the resistors by applying heat thereto to write data to the memory cell. The other heating element alters the resistance of the other resistor by applying heat thereto to erase data from the memory cell.