Abstract: Resonant sensors, preferably having floating bilayer symmetry, and their methods of use is determining the presence, amount or binding kinetics of an analyte of interest in a test sample are disclosed. The test sample may be a liquid or gas.

Abstract: A probe unit includes a gas sensor having multiple gas introduction bores for introducing a gas into an inside of the gas sensor, and a sensor holder inside of which the gas sensor is held and that is arranged inside of a duct so as to introduce an exhaust gas flowing in the duct into the gas sensor. A calibration gas flow channel is arranged in the sensor holder and has an opening at an inner surface of a side wall, surrounding the gas introduction bores of the gas sensor, of the sensor holder so as to supply a calibration gas to the gas sensor. A guide groove is arranged continuous to the opening of the calibration gas flow channel and arranged on the inner surface of the side wall along an arranging direction of the multiple gas introduction bores to face the multiple gas introduction bores.

Abstract: An object of the present invention is to provide a detection sensor and a vibrator which can offer improved sensitivity. The present invention uses a scheme in which no piezoelectric layer, drive electrode, or the like is provided on the surface of a vibrator 30 and in which the vibrator 30 is driven by an actuator 40 provided separately from the vibrator 30. The actuator 40 is of a cantilever type and is provided near a fixed end 30a of the vibrator 30. Vibration of the actuator 40 is transmitted to the vibrator 30 via a coupling beam 70. Thus, vibration of the vibrator 30 is prevented from being inhibited by a piezoelectric layer, a drive electrode, or the like. This improves the Q value of the vibrator 30 and thus the sensitivity of the detection sensor 10. Furthermore, if the detection sensor 10 is configured to offer a sensitivity equivalent to that of a conventional one, the size of the detection sensor 10 can be sharply reduced compared to that of the conventional one.

Abstract: A method and apparatus for the photo-acoustic identification and quantification of one or more analyte species present in a gaseous or liquid medium in low concentration utilizing a laser and a resonant optical cavity containing the medium and having within the cavity at least two partially transparent mirrors, one of which is a cavity coupling mirror and one of which is moveably mounted on an assembly responsive to an input signal.

Abstract: A photo acoustic trace gas detector for detecting a concentration of a trace gas in a gas mixture. The detector includes a light source for producing a light beam and a light modulator for modulating the light beam into a series of light pulses for generating sound waves in the gas mixture. The light modulator is arranged for modulating the light beam between a non-zero lower intensity level and a higher intensity level. An amplitude of the sound waves being a measure of the concentration. An optical cavity contains the gas mixture and amplifies a light intensity of the light pulses. A transducer converts the sound waves into electrical signals. A feedback loop with a photo detector for measuring the light intensity of the light pulses regulates the amplification of the light intensity in the optical cavity.

Abstract: A portable analytical system for detecting organic chemicals in water comprising a miniature preconcentrator and a SAW detector, the latter being characterized by a nanoporous carbon coating that provides improved response compared to prior art polymer coatings, particularly when detecting low concentrations of trihalomethane chemicals, such as chloroform and bromoform.

Abstract: A probe unit includes a gas sensor having multiple gas introduction bores for introducing a gas into an inside of the gas sensor, and a sensor holder inside of which the gas sensor is held and that is arranged inside of a duct so as to introduce an exhaust gas flowing in the duct into the gas sensor. A calibration gas flow channel is arranged in the sensor holder and has an opening at an inner surface of a side wall, surrounding the gas introduction bores of the gas sensor, of the sensor holder so as to supply a calibration gas to the gas sensor. A guide groove is arranged continuous to the opening of the calibration gas flow channel and arranged on the inner surface of the side wall along an arranging direction of the multiple gas introduction bores to face the multiple gas introduction bores.

Abstract: A sensing device for detecting an analyte is disclosed. In one aspect, the device includes at least one geometrical structure and at least two clamps provided for clamping the at least one geometrical structure on at least two ends of the geometrical structure. The at least one geometrical structure has at least one chemical responsive layer being absorbent or adsorbent for the analyte, and a support structure provided for at least partly supporting the at least one chemical responsive layer. The at least one chemical responsive layer has a varying effective spring constant which changes upon absorption or adsorption of the analyte.

Abstract: The present invention relates to a device and process for the quick and reliable online detection of triacetone triperoxide (TATP).

Abstract: An in-liquid-substance detection sensor that achieves size reduction and detection accuracy improvement includes a piezoelectric substrate, at least two SAW devices provided on one major surface of the piezoelectric substrate and each having at least one IDT electrode defining a sensing portion, outer electrodes provided on the other major surface of the piezoelectric substrate and electrically connected to the SAW devices through vias extending through the piezoelectric substrate, a channel-defining member provided on the one major surface of the piezoelectric substrate so as to surround the SAW devices and a region connecting the SAW devices to each other, thereby defining sidewalls of a channel, and a protective member bonded to the one major surface of the piezoelectric substrate with the channel-defining member interposed therebetween, thereby sealing the channel, the protective member having at least two through holes communicating with the channel.

Abstract: Methods and systems of detecting analytes using a microcantilever system are generally described. The microcantilever system generally includes micro- or nano-sized elements that can be electrostatically driven to resonance. Utilizing the disclosed devices and methods, direct electronic detection of the resonant frequency, changes of the resonant frequency, and associated phase signal of a micro- or nano-sized element can be utilized to measure the presence of a targeted analyte. The detection system of the present invention utilizes a non-contact microcantilever device. That is, the surface of the microcantilever (e.g., the surface of the resonating beam) does not bond or otherwise attach to an analyte or other chemical. Thus, the microcantilever device, including the resonating beam, can be kept in pristine condition during and even after repeated use.

Abstract: A sensor is provided having a diaphragm. One side of the diaphragm is arranged to be exposed to a fluid, to measure a characteristic of the fluid. Two supports are mounted on the diaphragm and a resonator is provided on the supports. The proportion of energy transferred from the resonator to the diaphragm is variable for the sensor to be used either as a viscosity/density sensor or as a pressure sensor.

Abstract: The present invention provides a novel analysis and detection device, which includes a separation unit for separating a plurality of single-component gases from the mixed components of a gaseous sample; a detection unit for producing a sound signal in response to a corresponding one of the single-component gases; and a signal receiving unit for transferring the sound signal into an electronic signal. The device of the present invention uses gas chromatography principle to separate mixed components of a gaseous sample, a plurality of single-component gases are formed to be detected, a sound signal is formed in response to a corresponding one of the single-component gases, and the components and their amounts are determined according to occurrence time and frequency of the sound signal. The present invention is applicable to a rapid detection and a quantitation analysis of a gas.

Abstract: A MEMS sensor includes at least one closed nodal anchor along a predetermined closed nodal path on at least one surface of a resonant mass. The resonant mass may be configured to resonate substantially in an in-plane contour mode. Drive and/or sense electrodes may be disposed within a cavity formed at least in part by the resonant mass, the closed nodal anchor, and a substrate.

Abstract: A resonant nanosensor apparatus associated with a functionalized monolayer for detecting carbon dioxide and a method of forming the same. A wafer including a sensing vibrating beam and a reference vibrating beam may be functionalized with a functional group in order to form a sensing self monolayer. The sensing self assembled monolayer may be configured by bridging oxygen or carbon atoms covalently bonded with respect to the vibrating beams. A liquid solution of hydrochloric acid may then be applied to the sensing self assembled monolayer at the surface of the reference beam by a direct printing process to obtain a reference monolayer. The liquid solution of HCl transforms the functional groups responsible for the carbon dioxide detection into protonated groups, which do not react with carbon dioxide, but possess visco-elastic properties similar to that of the sensing monolayer.

Abstract: A device for detecting helium in ambient atmosphere includes a resonator and a frequency detector. The resonator includes a piezoelectric film layer configured to absorb helium atoms. The frequency detector configured to detect a change in resonant frequency of the resonator when helium is absorbed into the piezoelectric film layer from the ambient atmosphere.

Abstract: There is provided a technique that can increase sensitivity of a resonator. A ratio Rb/Ra between an inner diameter Rb and an outer diameter Ra of the resonator 20 is appropriately selected, and thus there may be a fixed point where an r component (U(Ra) or U(Rb)) of displacement in a radial direction and an r component (V(Ra) or V(Rb)) of displacement in a tangential direction are 0 on an outer diameter portion or an inner diameter portion of the resonator 20. In this case, the resonator 20 is supported by a holding member 22 constituted by a single-span beam set so that a boundary condition on a side of the resonator 20 is pinned and a boundary condition on a side of an anchor that supports the resonator 20 is clamped at the fixed point, and this prevents vibration energy of the resonator 20 from being lost through the holding member 22, avoids a state to disturb a vibration mode, and achieves a sensor having high sensitivity.

Abstract: A nitrogenous gas sensor comprises a piezoelectricity plate which has a sensing surface; two transducers placed on the sensing surface of the piezoelectricity plate for transduction of electrostatic potential energy and acoustic energy, in order to generate surface acoustic waves on the piezoelectricity plate; and a sensing layer installed on the sensing surface of the piezoelectricity plate between the two transducers, which is consisted of polyaniline and tungsten oxide.

Abstract: A photo acoustic trace gas detector (100) is provided for detecting a concentration of a trace gas in a gas mixture. The detector (100) comprises a light source (101) for producing a light beam and a light modulator (103) for modulating the light beam into a series of light pulses at a chopping frequency for generating sound waves in the gas mixture. The amplitude of the sound waves is a measure of the concentration of the trace gas. The detector (100) further comprises an optical cavity (104a, 104b) with the gas mixture. The optical cavity (104a, 104b) amplifies the light intensity of the light pulses. A transducer (109) converts the sound waves into electrical signals. A feed back loop (110, 111, 113, 114) regulates a ratio of a length of the optical cavity (104a, 104b) and a wavelength of the light beam for amplifying the light intensity of the light pulses in the optical cavity (104a, 104b).

Abstract: Vibration of an electric submersible pump assembly is monitored to produce a vibration spectrum. The vibration spectrum is compared to a known vibration signature for a pump condition that precedes gas lock. The pump condition is at least one of an impeller rotating stall condition, a diffuser stall condition, a pre-surge condition, and percentage of free gas within the wellbore fluid. Operation of the pump is then adjusted in response to the similarity of the vibration spectrum to the vibration signature for the pump condition to prevent impending gas lock.

Abstract: A spectrophone assembly comprises a single detector chamber, a plurality of lasers, a gas inlet for supplying a gas sample to the single detector chamber, and at least one microphone. The detector chamber has an internal geometry arranged to be simultaneously acoustically resonant at a plurality of different resonant frequencies. Each laser operates at a different wavelength and is positioned to emit radiation into the single detector chamber, and is operable to emit radiation that is amplitude modulated at a frequency rate corresponding to a particular resonant frequency different from the resonant frequency of each other laser, simultaneously with each other laser. The microphone(s) are positioned in the single detector chamber so that each microphone is located at or near a maximum of a corresponding acoustic resonance defined by the internal geometry of the detector chamber.

Abstract: A sensor chip (1030) for gas has cells (200) for emitting and receiving ultrasound and is configured for a sufficiently large frequency range and for measuring concentration of at least one of the gas components based on at least two responses within the range. The frequency range can be achieved by varying the size of cell membranes (230), varying bias voltages, and/or varying air pressure for an array (205) of cMUTs or MEMS microphones. The sensor chip can be applied in, for example, capnography. A measurement air chamber (515) is implemented in the respiratory pathway (400), and it and/or the pathway may be designed to reduce turbulence in the exhaled breath (120) subject to ultrasound interrogation. The chip (1030) can be implemented as self-contained in the monitoring of parameters, obviating the need for off-chip sensors.

Abstract: The current invention relates to a conductivity-dielectric (CD) electrode design with apertures that allow compressional waves to propagate away from the surface of the acoustic wave device unimpeded. This prevents reflection of compressional waves that would interact with the viscosity sensor surface, thus altering the device response. It allows compressional waves to pass through, and allows the dual mode viscosity sensor responses to be utilized for density/viscosity/elasticity measurement and correlation. The invention further offers methods of instrumentation to detect unwanted reflections, to compensate, and to correct for the distortions caused by reflections. Finally, the invention provides a system and method for utilizing deliberately introduced reflections to obtain additional information, including fluid density.

Abstract: It is an object of the present invention to provide a technique that can realize improvement of sensitivity of a vibrator. A platform 50 to which a substance adheres or sticks is provided to be mechanically coupled to a vibrator 20 of a sensor via bridges 51. Sensitivity of the sensor is improved by causing the mass of a substance adhering or sticking onto the platform 50 as if the substance concentratedly adheres or sticks to places where the platform 50 is connected to the vibrator 20. It is preferable to connect, via the bridges 51, the platform 50 to places where the platform 50 vibrates integrally with the vibrator 20. For this purpose, it is preferable to mechanically couple, via the bridges 51, the platform 50 to regions where vibration occurs only in one of an r direction or a ? direction in the vibrator 20.

Abstract: An all-differential resonant nanosensor apparatus for detecting multiple gasses and method of fabricating the same. The nanosensor apparatus generally includes a sensing loop, a reference loop, and a mixer. A sensing self assembled monolayer (SAM) or an ultrathin solid monolayer may be deposited on a sensing resonant beam associated with the sensing loop to detect the presence of the gas. A reference self assembled monolayer or an ultrathin solid film may be deposited on a reference resonant beam that possess similar visco-elastic properties (e.g., temperature, humidity and aging) as the sensing monolayer with no sensing properties. A differential reading electronic circuit may be interconnected with each resonant beam pair for signal processing. A drift-free frequency signal per each gas may be obtained by subtracting the frequency response from the sensing loop and the reference loop.

Abstract: Apparatuses and methods for determining the concentration of an analyte gas in a gas stream with a sensor are described. The analyte gas sensor may include a mass-sensitive resonator and a diffusion barrier. The mass-sensitive resonator may be coated with an absorptive material which is reactive with an analyte gas, such as NOx. The diffusion barrier may be positioned to limit a gas flow with the analyte gas towards the absorptive material, and a ratio of the diffusion time of the gas flow through the diffusion barrier to the reaction time of the analyte gas with the absorptive material may be from about 0.1 to about 100.

Abstract: A photo acoustic detection cell (6) is located within the optical cavity (3) of a cavity enhanced absorption spectroscopy apparatus (3,4,5). When a sample in the cell (6) absorbs radiation from a pulsed radiation beam coupled into the cavity (3) pressure waves are generated that are detected by a microphone (9). A detected signal (10) output by the microphone (9) may be processed to determine a value for the concentration of an absorber in the sample.

Abstract: A piezoelectric bimorph cantilever is used for determining physical parameters in a gaseous or liquid environment. The sensor works as a driven and damped oscillator. Contrary to common cantilever sensor systems, the piezoelectric film of the bimorph cantilever acts as both a sensor and an actuator. Using at least two resonance mode of the bimorph cantilever, at least two physical parameters can be measured simultaneously in a gas or a liquid. An optimized piezoelectric cantilever and a method to produce the cantilever are also described.

Abstract: The design and synthesis of a matrix nanocomposite containing amino carbon nanotubes used as a functionalized sensing layer for carbon dioxide detection by means acoustic wave sensing devices, e.g., SAW/BAW devices. These sensing materials contain a type of amino carbon nanotubes (single walled or multi-walled) and a polymer (or other compounds) which are sensitive to carbon dioxide in the acoustic wave sensing device based gas sensors. The sensitivity of the matrix consisting of the amino carbon nanotubes and a polymer (or other compounds) is ensured by the presence of amino groups which can react at room temperature with CO2 in a reversible process to form carbamates.

Abstract: An object of the present invention is to provide a sensing instrument capable to detect a substance existing in a very small quantity, such as environmental pollutants, instantly with a high degree of precision. As a specific means for solving the problem, a frequency signal from a crystal oscillator is sampled using a frequency signal from a reference clock generating part, the sampling value is outputted in a digital signal, quadrature detection is conducted with the digital signal for a frequency signal corresponding to the output signal, the rotational vector rotating at a frequency corresponding to the difference between the frequency of the frequency signal and the frequency of a sinusoidal wave used for the quadrature detection is taken out, and the variation of the frequency is detected by detecting the velocity of the rotational vector based on the respective sampling values.

Abstract: An ionic liquid bound on an exposed surface of a device such as for detecting organic chemicals, preferably a gas sensor is described. The gas sensor can operate at high temperatures with a fast linear response which is also reversible. At high temperatures, the frequency change (?f) versus concentration (C) curve mirrors the Henry's gas law, such that the concentration of a gas sample in liquid solvent is proportional to the concentration or partial pressure of the sample in gas phase. A single gas sensor, or an array of sensors, can be used for the detection and quantitative analysis of gas vapors.

Abstract: Acoustic sensing utilizing a bridge structure coupled about a portion of at least two sides of said bridge to a base substrate, wherein said bridge includes a piezoelectric section and has at least one active acoustic region proximate said bridge. A sensing material is disposed on at least a portion of at least one surface of the bridge, wherein the bridge produces stress effects measurable by an acoustic wave device located in the active acoustic region. According to one embodiment, the stress effects are measured by an acoustic wave device to sense a target matter. As target molecules accumulate on a sensing film affixed to at least a portion of the bridge, stress is produced in the bridge inducing a frequency change measured by an acoustic wave device.

Abstract: A system and a method for providing information on two of the three variables, density (?), viscosity (?), and elastic modulus (c) of a fluid, such that independent knowledge of one variable allows the remaining two variables to be measured by a single sensor. The present invention relies on the interaction of a predominantly shear horizontal acoustic wave device (“quasi-shear-horizontal”) with the fluid, so as to measure subtle differences in the interaction of two or more acoustic resonance states or waveguide modes of a multi-mode resonator or waveguide, and to derive the desired fluid characteristics therefrom. The most preferred embodiment is a dual-mode coupled resonator filter geometry with one resonant mode having a high degree of symmetry and the other having a high degree of anti-symmetry.

Abstract: The present invention provides a hexagonal, delay line surface acoustic wave device fabricated on a a piezoelectric substrate, such as lithium tantalate, coated with an insulating waveguide on to which a sensing film, such as an anti-human Interleukin-6 biosensor film, is physically absorbed. The acoustic waves that propagate along the delay lines of the SAW device provide for detection of biological species along one delay line and simultaneously provide for removal of non-specifically bound protein along the remaining delay lines.

Abstract: An assembly design for an oscillating resonator-based sensor where an oscillating crystal resonator such as a quartz crystal resonator is rigidly affixed or ‘mounted’ onto a solid substrate in such a fashion that the resonator can either rest flush against the substrate surface or upon a rigid mounting adhesive. Once cured, the mounting adhesive forms a liquid tight seal between the mounted resonator and the substrate such that only the sensing electrode surface will be exposed to fluids applied to the front side of the substrate. The mounted resonator assembly is designed in such a way that it can be interfaced with a fluid delivery system to form a liquid tight chamber or flow cell around the mounted resonator without incurring additional physical impact upon the mounted resonator.

Abstract: A user-friendly photoacoustic spectroscopy (PAS) system and process (technique) provides an open-field PAS instrument, unit and device to remotely sense explosives, chemicals and biological agents. The PAS system and process can include: a pulsed tunable laser, such as a CO2 laser, a reflector, such as a parabolic reflector, an acoustic reverberant resonator in which a microphone is installed, and a data acquisition and analysis system.

Abstract: A gas sensor comprises a first surface-acoustic-wave device, at least one further surface-acoustic-wave device, and a control device. The first surface-acoustic-wave device includes a piezoelectric substrate, a pair of transducers and an external circuit. The pair of transducers consists of a first transducer and a second transducer, and they are formed on two sides of the piezoelectric substrate. The first transducer is utilized to generate a surface acoustic wave on the piezoelectric substrate. The external circuit electrically connects to the pair of transducers. At least one further surface-acoustic-wave device includes at least one first surface-acoustic-device and a sensing porous thin film of which two sides are formed on the pair of the transducers. The control device is utilized to control only one external circuit to become activated at one time.

Abstract: A disclosed chemical detection system for detecting a target material, such as an explosive material, can include a cantilevered probe, a probe heater coupled to the cantilevered probe, and a piezoelectric element disposed on the cantilevered probe. The piezoelectric element can be configured as a detector and/or an actuator. Detection can include, for example, detecting a movement of the cantilevered probe or a property of the cantilevered probe. The movement or a change in the property of the cantilevered probe can occur, for example, by adsorption of the target material, desorption of the target material, reaction of the target material and/or phase change of the target material. Examples of detectable movements and properties include temperature shifts, impedance shifts, and resonant frequency shifts of the cantilevered probe. The overall chemical detection system can be incorporated, for example, into a handheld explosive material detection system.

Abstract: This invention relates to methods and apparatus of quantifying the portion of a gas in a specific nuclear symmetric state. Specifically, the invention is directed to the measurement of the speed of sound in an unknown sample and comparing it to astandard.

Abstract: The invention relates to a system and method for detecting one or more gases or gas mixtures and/or for measuring the concentration of one or more gases or gas mixtures, said system comprising at least a light source, a sample space, a reference chamber, and a measuring chamber. The measuring chamber is supplied with a gas to be detected or measured. In addition, the measuring chamber is provided with a pressure sensor for detecting a photoacoustic signal generated in the measuring chamber. The pressure sensor comprises either a door, whose movement is measured without contact, or a sensor, whose movement is measured optically.

Abstract: A Monolithic Antenna Excited Acoustic Transduction (MAEAT) device is fabricated by photolithographically depositing a metallic antenna on one side of a piezoelectric crystal substrate.

Abstract: A cantilever type sensor includes a cantilever, an actuator that oscillates the cantilever, and a sensor provided at the cantilever so as to detect an oscillation condition of the cantilever. Further, the cantilever type sensor includes a control unit that controls the actuator so as to cause the cantilever to be subjected to pulse excitation, and a measurement unit that measures a physical quantity related to a measurement object, based on a change in pulse response detected in the sensor.

Abstract: An acoustic wave sensor assembly includes piezoelectric material, a first acoustic wave resonator element structure mounted on the piezoelectric material for interacting with an electrical signal, the acoustic wave resonator element structure being operable to interact with an acoustic wave propagating within the piezoelectric material to produce a first frequency response. Further acoustic wave resonator element structures are mounted on the piezoelectric material for interacting with electrical signals, the further acoustic wave resonator element structures being operable to interact with further acoustic waves propagating within the piezoelectric material to produce subsequent frequency responses. The first acoustic wave resonator element structure and further acoustic wave resonator element structures are combined to form a ladder or lattice filter network to produce an overall frequency response.

Abstract: A system and method for analyzing a target analyte gas concentration using a photoacoustic spectroscopy cell comprising: i) a modulatable light source which provides optical radiation at an absorption wavelength of a target analyte; ii) a resonant acoustic chamber for containing said analyte; iii) a microphone positioned within said chamber whereby the acoustic reactance of the microphone is a substantial factor in determining the acoustic resonant frequency of the acoustic chamber and where the magnitude of the acoustic reactance of the microphone is at least two times the acoustic resistance of the microphone.

Abstract: A sensor for the measurement of the hydrocarbon content in a flow of gas in a purge line. The sensor can measure the hydrocarbon content in the flow of gas in the purge line from a hydrocarbon storage device to an internal combustion engine. The sensor has at least one heating element and at least one thermal detector, with the heating element heating the flow of gas while the thermal detector determines the temperature of the flow of gas, which temperature is evaluated as a measurement of the hydrocarbon content in the flow of gas.

Abstract: Systems and methods for detecting a gaseous analyte utilize a micromechanical piezoelectric resonator having a functionalization layer configured to bind with the gaseous analyte. The functionalization layer may include a layer of carbon nanotubes affixed to the resonator and coated with biopolymers configured to bind with the gaseous analyte. The gaseous analyte may be detected by operating the micromechanical piezoelectric resonator and functionalization layer in the presence of the gas, detecting a change in the resonant frequency of the resonator, and determining the concentration of the gaseous analyte from the change in resonant frequency. Finally, the layer of carbon nanotubes may be grown on the piezoelectric resonator by depositing a catalyst on a piezoelectric structure, heating the piezoelectric structure and the catalyst to enhance the growth of the carbon nanotubes, and growing the carbon nanotubes at growth sites on the piezoelectric structure.

Abstract: The invention concerns a gas analyzer, which comprises: an electromagnet that has an air gap; a power source for supplying cyclically variable electrical current/voltage to said electromagnet; a sample gas conduit and a reference gas conduit opening into said air gap; an exit conduit communicating with said air gap for removing the intermixed sample and reference gases; pressure detecting microphone or microphones connected to said sample gas conduit and to said reference gas conduit for sensing gas pressures at a first acoustic measuring frequency in the respective conduits giving at least one acoustic pressure signal component; and electronics connected to said microphone(s) to receive said acoustic pressure signal component or components to form at least a first intermediate output signal describing content of a paramagnetic gas component in the sample gas.

Abstract: An electronic microbalance made in a semiconductor body accommodating an oscillating circuit adjacent to a diaphragm. A stack formed by a first electrode, a second electrode, and a piezoelectric region arranged between the first and the second electrode extends above the diaphragm. Any substance that deposits on the stack causes a change in the mass of the microbalance and thus in the resonance frequency of a resonator formed by the microbalance and by the oscillating circuit and can thus be detected electronically. A chemical sensor is obtained by forming a sensitive layer of a material suitable for binding to target chemicals on the stack. The sensitivity of the microbalance can be increased by making the first electrode of molybdenum so as to increase the piezoelectric characteristics of the piezoelectric region.

Abstract: All-optical photoacoustic spectrometer sensing systems (PASS system) and methods include all the hardware needed to analyze the presence of a large variety of materials (solid, liquid and gas). Some of the all-optical PASS systems require only two optical-fibers to communicate with the opto-electronic power and readout systems that exist outside of the material environment. Methods for improving the signal-to-noise are provided and enable mirco-scale systems and methods for operating such systems.

Abstract: A piezoelectric bimorph cantilever is used for determining physical parameters in a gaseous or liquid environment. The sensor works as a driven and damped oscillator. Contrary to common cantilever sensor systems, the piezoelectric film of the bimorph cantilever acts as both a sensor and an actuator. Using at least two resonance mode of the bimorph cantilever, at least two physical parameters can be measured simultaneously in a gas or a liquid. An optimized piezoelectric cantilever and a method to produce the cantilever are also described.