Title :
Solid State Gas Sensor for Fast Carbon Dioxide Detection
Author :
Herrán, J. ; Mandayo, G.G. ; Castaño, E.
Author_Institution :
CEIT & Tecnun (Univ. of Navarra), San Sebastian
Abstract :
Some promising results on the behaviour of BaTiO3-CuO sputtered thin films under carbon dioxide atmospheres are presented. The sensing material response to different CO2 concentrations is due to a reversible reaction based on the presence of BaCO3 in the material. The measurement of impedance changes allows monitoring the variation in CO2 concentration. Resistance and capacitance variations are closely related to work function changes in the p-n heterojunction between BaTiO3 and CuO. The frequency response shows spatial-charge and relaxation phenomena that permit finding an optimal working frequency range. The sensing layer thickness influence in the response is reported and also the influence of Ag as additive in the film.
Keywords :
barium compounds; carbon compounds; chemical variables measurement; copper compounds; electric impedance measurement; frequency response; gas sensors; p-n heterojunctions; silver; thin films; work function; Ag; BaCO3; BaTiO3-CuO; capacitance variations; carbon dioxide detection; frequency response; impedance measurement; p-n heterojunction; relaxation phenomena; resistance variations; sensing material; solid state gas sensor; sputtered thin films; work function; Atmosphere; Atmospheric measurements; Capacitance; Carbon dioxide; Electrical resistance measurement; Gas detectors; Impedance measurement; Monitoring; Solid state circuits; Sputtering; BaTiO3-CuO; CO2; gas sensor;
Conference_Titel :
Solid-State Sensors, Actuators and Microsystems Conference, 2007. TRANSDUCERS 2007. International
Conference_Location :
Lyon
Print_ISBN :
1-4244-0842-3
Electronic_ISBN :
1-4244-0842-3
DOI :
10.1109/SENSOR.2007.4300296
