| 摘要 |
PROBLEM TO BE SOLVED: To measure the concentration of nonpolar gas accurately by correcting the measurements of concentration obtained through weight measurement based on the permittivity of a polymer film thereby eliminating the effect of fluctuation of relative humidity. SOLUTION: A pair of electrodes 4 for measuring the capacitance are formed on the surface of a polymer film 2 covering an oscillatory (quartz) crystal 1 and a top electrode 5 passing a gas to be measured is provided. The crystal 1 is oscillated by means of a pair of electrodes 3 and the weight of polymer film 2 is determined based on the variation of frequency thus measuring the concentration of nonpolar gas, e.g. CO., adsorbed/absorbed by the polymer film 2. Furthermore, capacitance of the sensor structure, i.e., the permittivityεof polymer film 2, is measured by means of the pair of electrodes 4 and the measurements of concentration obtained through weight measurement are corrected thus eliminating the effect of humidity.
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