INSTITUTO DE QUIMICA, FISICA DE LOS MATERIALES, MEDIOAMBIENTE Y ENERGIA
Unidad Ejecutora - UE
Conductivity in SnO2 polycrystalline thick film gas sensors: tunneling electron transport and oxygen diffusion
C.M. ALDAO, F. SCHIPANI, M.A. PONCE, E. JOANNI, Y F.J. WILLIAMS
SENSORS AND ACTUATORS B-CHEMICAL
ELSEVIER SCIENCE SA
Lugar: Amsterdam; Año: 2014 vol. 193 p. 428 - 428
Conduction mechanisms in polycrystalline SnO2thick sensing films were investigated by means of DCelectrical resistance during heating?cooling cycles. Samples were maintained at relatively high temper-atures in H2or O2ambient atmospheres before performing electrical measurements under vacuum orbefore performing XPS measurements in order to determine band bending. Results suggest that inter-grains present Schottky barriers that are responsible for the observed conductivities regardless of gaspre-treatment. Oxygen diffusion modulates barrier widths affecting conductivity through tunnelingtransport. The electrical response to subsequent exposure to an oxygen atmosphere is consistent withour interpretation.