Fast Gas Sensing Using an Integrated Synthetic Jet Actuator

A miniature (millimeter-scale) synthetic jet actuator is integrated with a chemical gas sensor (chemFET) to effect inhalation and exhalation of ambient gas samples and induce small-scale mixing at the surface of the sensor. The fluidically integrated jet transports ambient fluid into the jet/sensor assembly through integrated fluid channels, impinges the sample fluid on the sensing element, and finally ejects the sample fluid to the ambient. The response of the sensor in the presence of the active jet is compared to its response when the jet is inactive. The jet actuator directs entrained ambient air toward the active surface of the sensor, and the impingement of sample gas onto the surface of the sensor results in faster response time. Because the operating characteristics of the integrated synthetic jet actuator can be easily optimized for specific configurations, it is concluded that jet-assisted sampling and sample transport coupled with turbulent impingement can offer significant advantages for gas sensor systems