Effects of Materials Chemistry and Morphology on Conductometric Sensor Signals

Douglas C. Meier and Steve Semancik

Observation of conductance changes in material films upon their interactions with gas phase molecules is the basis of operation of the chemical microsensors being developed in the Chemical Sciences and Technology Laboratory at NIST. These interactions are based upon the identity of the analyte molecule, the operating temperature of the sensor device, and the physical and chemical properties of the sensing film. In this study of the performance of chemical vapor deposition (CVD) TiO2, SnO2, layered oxides, and Ru-doped oxide sensing films, we demonstrate the degrees to which variations in material film thickness, morphology, and chemical composition affect a sensorís response to a given analyte. We further demonstrate that these material-dependent responses can be used as a basis for analyte identification.

Douglas C. Meier

836.04 (CSTL Process Measurements Division, Process Sensing Group)

Building 221 Office A315

MS 8362

Office (301) 975-4619

Fax (301) 975-2643

dmeier@nist.gov

Sigma Xi member

Poster in Materials Division