INVESTIGADORES
WILLIAMS Federico Jose
artículos
Título:
Conductivity in SnO2 polycrystalline thick film gas sensors: Tunneling electron transport and oxygen diffusion
Autor/es:
C. M. ALDAO; F. SCHIPANI; M. A. PONCE; E. JOANNI; F. J. WILLIAMS
Revista:
SENSORS AND ACTUATORS B-CHEMICAL
Editorial:
ELSEVIER SCIENCE SA
Referencias:
Lugar: Amsterdam; Año: 2014 vol. 193 p. 428 - 433
ISSN:
0925-4005
Resumen:
Conduction mechanisms in polycrystalline SnO2 thick sensing films were investigated by means of DC electrical resistance during heating?cooling cycles. Samples were maintained at relatively high temper- atures in H2 or O2 ambient atmospheres before performing electrical measurements under vacuum or before 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 gas pre-treatment. Oxygen diffusion modulates barrier widths affecting conductivity through tunneling transport. The electrical response to subsequent exposure to an oxygen atmosphere is consistent with our interpretation.
