It is proposed a sensor for measuring a gas property, wherein the sensor comprises a semiconductor die, wherein the semiconductor die comprises a reference cavity and a measuring cavity, wherein a reference sensor element is arranged in the reference cavity, wherein a measuring sensor element is arranged in the measuring cavity, wherein the reference cavity is sealed from ambient gas, wherein the measuring cavity is fluidly connected to ambient gas. Further it is proposed a method for manufacturing such a sensor.

A system and method of determining a target gas concentrations in a fluid environment using a gas sensor that improves the efficiency and accuracy of the gas sensor's measurements by taking measurements of electrical characteristics of the gas sensor at different temperatures, taking measurements during a transition between a first temperature and a second temperature, taking more frequent measurements, detecting when the gas sensor has reached equilibrium, using multiple sensors, accounting for offsets and drifts, reducing the time the sensor is not live, using various algorithms, or any combination thereof.

A gas detection system includes a sensor unit that outputs a voltage corresponding to a concentration of a specific gas, a supply unit, and a control unit. The supply unit is capable of supplying a sample gas and a purge gas to the sensor unit. The control unit controls the supply unit to alternately supply the sample gas and the purge gas to the sensor unit. The control unit acquires a voltage waveform output by the sensor unit and detects a type and concentration of a gas contained in the sample gas, using a multiple regression analysis using characteristics of the voltage waveform as explanatory variables.

The present application is directed to a method of measuring the concentration of radicals in a gas stream which includes the steps of flowing a radical gas stream emitted from at least one radical gas generator to at least one processing chamber, providing at least one sampling reaction module having at least one sampling tube therein, establishing a reference temperature of the sampling tube with at least one thermal control module, diverting a portion of the radical gas steam from the radical gas generator into the sampling tube, reacting at least one reagent with at least one radical gas within a defined volume of the radical gas stream thereby forming at least one chemical species within at least one compound stream, the compound stream flowing within the sampling tube, measuring a change of temperature of the sampling tube due to interaction of the chemical species within the compound stream and the sampling tube with sensor module, and calculating a concentration of the chemical species within the compound stream flowing within the sampling tube based on the measured temperature change of the sampling tube.

An apparatus comprises an integrated circuit that includes an input to receive an electrical input signal from an electronic sensor, wherein the input signal includes a direct current (DC) offset and a varying signal component; a digital-to-analog converter (DAC) circuit configured to subtract the DC offset from the input signal; a programmable gain amplifier (PGA) operatively coupled to the DAC circuit, wherein the PGA circuit is configured to apply signal gain to the varying signal component of the input signal; and a measurement circuit configured to generate a measure of the varying signal component.

An impedance in an electrochemical gas sensor can be measured by connecting at least one pin in an integrated circuit to at least one electrode in an electrochemical gas sensor, using a damping capacitor to connect the at least one pin in the integrated circuit to an electrical ground, applying a voltage to the electrochemical gas sensor to provide a bias voltage to at least one electrode in the electrochemical gas sensor, receiving a current from at least one electrode in the electrochemical gas sensor, determining a measured gas amount from the received current, activating a switch located within the integrated circuit to isolate the damping capacitor from the at least one pin in the integrated circuit, and measuring an impedance of the electrochemical gas sensor using an excitation signal while the at least one damping capacitor is isolated from the at least one electrode in the electrochemical gas sensor.

A system for low power chemical sensing can include a voltage shift unit which receives a voltage signal from a chemical sensor unit. The voltage signal can be determined by a concentration of an analyte. The voltage shift unit can transform the voltage signal to an input voltage signal, and send the input voltage signal to a plurality of frequency selective surface (FSS) units of an FSS array. The FSS array can communicate a radio frequency (RF) signal in an Institute of Electrical and Electronics Engineers (IEEE) S band with a resonant frequency based on the input voltage to provide the concentration of the analyte.

A detection system includes at least one sensor configured to measure a presence of airborne particles and at least one amplifier circuit in communication with the at least one sensor. The amplifier circuit is configured to monitor a charge generated by the at least one sensor over a time interval. The system further includes a controller configured to monitor the charge accumulated in the at least one amplifier circuit from the at least one sensor at the time interval. In response to the charge of the at least one amplifier circuit, the controller detects the presence of the airborne particles.

A nanomaterial-based gas sensor system comprising a low voltage circuitry which includes a transducer to detect changes in electrical properties of a multi-channel gas sensor array, analog signal conditioning, and an A/D conversion to provide a signal to a digital back-end.

This document provides methods, devices, and systems for detecting the presence, absence, or amount of one or more analytes. For example, this document provides methods for using graphene-based sensors to detect one or more analytes (e.g., proteins, nucleic acids, intact cells, intact viruses, intact microorganisms, and/or chemicals).