Nature of the Schottky-type barrier of highly dense SnO[sub 2] systems displaying nonohmic behavior.

The electrical characteristics of highly dense SnO[sub 2] ceramic varistors are believed to be caused by the existence of potential barriers at the grain boundary. A complex plane analysis technique (to eliminate the influence of trapping activity associated with the conductance term observed via depression angle of a semicircular relaxation in the complex capacitance plane), allied with an approached Mott-Schottky model, are used to demonstrate that the potential barriers at the grain boundary are Schottky-type barriers in SnO[sub 2] varistors such as those observed in the traditional ZnO varistor. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]