Title :
Analysis on the frequency characteristics for conduction mechanism in zinc oxide varistors
Author :
Oh, Myung Hwan ; Kim, Myung Sik ; Koo, Ja Yoon
Author_Institution :
Korea Adv. Inst. of Sci. & Technol., Seoul, South Korea
Abstract :
The frequency characteristics of ZnO varistors were investigated in frequency range from 5 Hz to 1 GHz. Three resonant points were observed in the frequency dependence of the real part of the varistor impedance multiplied by frequency. This result suggests that a suitable barrier model of a ZnO varistor might be the double Schottky barrier model with a sandwiched intergranular barrier, by means of which the nonohmic properties of ZnO varistors could be explained. The current-voltage characteristics of the ZnO varistor were also investigated in the current range from 100 nA to 10 mA, showing that the varistor behavior is mainly controlled by the reverse-biased Schottky barrier in the voltage region below the threshold voltage, as well as by the forward-biased Schottky barrier in the voltage region above the threshold voltage
Keywords :
II-VI semiconductors; Schottky effect; varistors; zinc compounds; 100 nA to 10 mA; 5 Hz to 1 GHz; ZnO varistors; current-voltage characteristics; double Schottky barrier model; nonohmic properties; semiconductor; threshold voltage; Current-voltage characteristics; Frequency dependence; Impedance; RLC circuits; Resonance; Resonant frequency; Schottky barriers; Threshold voltage; Varistors; Zinc oxide;
Conference_Titel :
Conduction and Breakdown in Solid Dielectrics, 1989., Proceedings of the 3rd International Conference on
Conference_Location :
Trondheim
DOI :
10.1109/ICSD.1989.69209
