Ultrasensitive, ultrathin vapor sensors and arrays

Inventors

Gregory, Otto J. • RICCI, Peter P.

Assignees

Trace Sensing Technologies Inc

Abstract

Ultrasensitive, ultrathin thermodynamic sensing platforms for the detection of chemical compounds at trace levels are disclosed. Embodiments of the ultrathin sensor comprise substrate, adhesion, microheater, and catalyst layers. A sensor array may include a plurality of sensors each having a different catalyst. When a sensor array exposed to an analyte, each of the various sensors of the array may experience an endothermic reaction, an exothermic reaction, or no reaction. A comparison of the reaction results to data comprising previously-obtained reaction results may be used to determine information on the analyte. Advantageously, these ultrathin vapor sensors utilize less power and provide greater sensitivity, and may be used to detect and identify analytes at the PPT level. Specialized sensors configured to detect analytes falling into a certain category (e.g., explosives, drugs and narcotics, biomarkers, etc.) are disclosed, as well as general purpose sensors capable of detecting analytes from a plurality of categories.

Core Innovation

An ultrasensitive ultrathin thermodynamic vapor sensor is described that includes an ultrathin substrate and a microheater integrated with a catalyst layer. The sensor detects a vapor analyte by using thermal responses that result from reactions between the analyte and the catalyst layer, and detection is based on controlling one or more setpoint temperatures and compensating thermal effects by varying applied heater power.

A first sensor with a catalyst layer is compared against a second sensor or a reference sensor lacking the catalyst to provide a basis for interpretation. The disclosed detection approach uses endothermic or exothermic heat effects determined from power variation required to maintain setpoint temperature(s), and a controller delivers power to heat sensors to setpoint temperature(s) while varying power to account for thermal responses caused by reactions between the analyte and the first catalyst.

The existence, identity, and/or concentration of the analyte is determined based on the varied power. In a sensor array configuration, multiple sensors enable analyte responses to be represented as distinct thermodynamic patterns, and catalyst libraries with different catalyst materials support analyte fingerprinting by comparison against a database of known thermal responses.

The document also describes ultrathin multilayer structures employing ultrathin YSZ and porous aerogel substrates, including catalyst layer(s) that undergo chemical reaction when exposed to an analyte that produces an endothermic or exothermic response. A heat effect is determined by comparing a second power level used to maintain the setpoint after reaction begins to a first power level used to reach the setpoint temperature.

Claims Coverage

The independent claims include three inventive aspects: a detection device using a catalyst sensor and a reference sensor controlled by a controller that varies heater power at setpoint temperatures; a method using a sensor array with catalyst-reacting and non-catalyst sensors where power variation at setpoints determines analyte information; and a detection device using first and second power levels to reach and then maintain a setpoint temperature during an endothermic or exothermic catalytic reaction, where a heat effect is determined by comparing the power levels. Overall, there are three independent claims with power-varying thermodynamic detection based on catalyst-mediated heat effects.

Across the independent claims, the common inventive concept is thermodynamic detection using catalyst-mediated endothermic/exothermic heat effects represented as the power variation needed to maintain one or more setpoint temperatures, optionally using a reference sensor and enabling analyte information to be derived from comparing first and second power levels.

Stated Advantages

Documented Applications