Key points are not available for this paper at this time.
The interface states at the grain boundaries in ZnO varistors are quantitatively investigated by Isothermal Capacitance Transient Spectroscopy (ICTS). At first we describe the formulation of ICTS signals caused by the interface states, and then analyze the observed results. They were characterized as monoenergetic interface states laid at 0.77eV below the conduction band. The density and the capture cross section of the interface states were calculated as 1.1×1012cm-2 and 1.1×10-16cm2, respectively. The level of the interface states which capture electrons at zero-biased voltage was considered to be identical with that detected by ICTS measurements.
TSUDA et al. (Wed,) studied this question.