Influence of frozen distributions of oxygen vacancies on tin oxide conductance

G. BLAUSTEIN, M.S. CASTRO, Y C.M. ALDAO

SENSORS AND ACTUATORS B-CHEMICAL

Año: 1999 vol. 55 p. 33 - 37

0925-4005

Resistivity transients of SnO2 sintered pellets at step isothermal changes in oxygen pressure are investigated. It is found that different thermal treatments in sample preparation give rise to diverse behaviors in transient responses. These responses indicate that modulation of the Schottky barriers heights is not enough to explain the observed results. It is proposed that grain sizes and widths of the depletion layers are responsible for the observed results and that an oxygen diffusion process into the tin oxide grain plays a significant role accounting for the observed conductance changes.