Abstract: Methods and apparatus for etching materials using tetramethylammonium hydroxide (TMAH) are described. The methods may involve including an additive when applying the TMAH to the material to be etched. The additive may be a gas, and in some situations may be clean dry air. The clean dry air may be provided with the TMAH to minimize or prevent the formation of hillocks in the etched structure. Apparatus for performing the methods are also described.

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: 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 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.

Abstract: A micro-electrochemical sensor contains magnetic compounds inserted within a substrate that exert a magnetic force of attraction on paramagnetic beads held in contact with an electrode. The magnetic compounds can be contained within a fluid that is introduced into a void in the substrate. The electrode can be spaced apart from the magnetic compounds by a dielectric multi-layer membrane. During the fabrication process, different layers within the membrane-electrode structure can be tuned to have compressive or tensile stress so as to maintain structural integrity of the membrane, which is thin compared with the size of the void beneath it. During a process of forming the structure of the sensor, the tensile stress in a TiW adhesion layer can be adjusted to offset a composite net compressive stress associated with the dielectric layers of the membrane. The membrane can also be used in forming both the electrode and the void.

Abstract: Embodiments of the present disclosure are related to MEMS devices having a suspended membrane that are secured to and spaced apart from a substrate with a sealed cavity therebetween. The membrane includes openings with sidewalls that are closed by a dielectric material. In various embodiments, the cavity between the membrane and the substrate is formed by removing a sacrificial layer through the openings. In one or more embodiments, the openings in the membrane are closed by depositing the dielectric material on the sidewalls of the openings and the upper surface of the membrane.

Abstract: A micro-electrochemical sensor contains magnetic compounds inserted within a substrate that exert a magnetic force of attraction on paramagnetic beads held in contact with an electrode. The magnetic compounds can be contained within a fluid that is introduced into a void in the substrate. The electrode can be spaced apart from the magnetic compounds by a dielectric multi-layer membrane. During the fabrication process, different layers within the membrane-electrode structure can be tuned to have compressive or tensile stress so as to maintain structural integrity of the membrane, which is thin compared with the size of the void beneath it. During a process of forming the structure of the sensor, the tensile stress in a TiW adhesion layer can be adjusted to offset a composite net compressive stress associated with the dielectric layers of the membrane. The membrane can also be used in forming both the electrode and the void.

Abstract: Methods and apparatus for etching materials using tetramethylammonium hydroxide (TMAH) are described. The methods may involve including an additive when applying the TMAH to the material to be etched. The additive may be a gas, and in in some situations may be clean dry air. The clean dry air may be provided with the TMAH to minimize or prevent the formation of hillocks in the etched structure. Apparatus for performing the methods are also described.

Abstract: Temperature variations in a patient's body can lead to inaccurate glucose readings. To compensate for changes in temperature, the temperature at a glucose sensing site can be sensed using a thermocouple. A compensated glucose level can be determined based on the temperature and the sensed glucose level. A glucose sensing device is described that includes a glucose sensor having a working electrode and a thermocouple having a junction positioned proximate the working electrode, with both the glucose and temperature sensors including the same metals.