| 摘要 |
<p>A sensor for detection of a trace fluid component in a fluid environment, comprising: a piezoelectric crystal having a fundamental resonant frequency in response to an applied oscillating electric field; a coating on the piezoelectric crystal of a sensor material which is reactive with the trace fluid component to yield a solid interaction product; means for applying an oscillating electric field to the piezoelectric crystal which generates an output resonant frequency therefrom; means for (i) sampling the output resonant frequency of the piezoelectric crystal while the oscillating electric field is applied thereto, (ii) determining the change in resonant frequency from the fundamental resonant frequency that occurs on formation of the solid interaction product when the sensor material interacts with the trace fluid in the fluid environment, and (iii) generating an output indicative of the presence of the trace fluid component in the environment; and means for flowing fluid from the fluid environment to the coating on the piezoelectric crystal so that the trace fluid component when present reacts with the coating to form the solid interaction product; wherein the coated piezoelectric crystal exhibits a frequency response rate to the trace fluid component in the range of from about 0.001 to about 1000 milleHertz/min./(part-per-million of the fluid component). The sensor may be utilized for sensing of breakthrough in dry scrubbing of gases in semiconductor manufacturing, as well as for sensing of contaminant and hazardous gas species in ambient fluid environments, for environmental monitoring applications.</p> |
