Microstructural analysis of varistors prepared from nanosize ZnO

Quality assessment of ZnO-based varistors by 1/f noise

Noise has been used as a diagnostic tool of surge arrester varistor structures comprising of ZnO grains of various type and size. The physical and electrical properties of the measured samples have been described. In the experimental study, the applied measurement system and the results of noise measurements for the selected structures of varistors designed for the continuous working voltage 28...

Optical and microstructural properties of ZnO/TiO2 nanolaminates prepared by atomic layer deposition

ZnO/TiO2 nanolaminates were grown on Si (100) and quartz substrates by atomic layer deposition at 200°C using diethylzinc, titanium isopropoxide, and deionized water as precursors. All prepared multilayers are nominally 50 nm thick with a varying number of alternating TiO2 and ZnO layers. Sample thickness and ellipsometric spectra were measured using a spectroscopic ellipsometer, and the parame...

Effect of Step Sintering on Breakdown Voltage of Varistors Prepared from Nanomaterials

The Role of Polypyrrole in Electrical Properties of ZnO-Polymer Composite Varistors

Composite films on the base of ZnO with different weight percentages of polypyrrole have been prepared using the hot pressing method and their current-voltage characteristics have been studied. Results show that the films have nonlinear varistor behavior and can be used to protect sensitive circuits from 110V up to 350V overvoltages. It is found that the higher the content...

LOW-TEMPERATURE SINTERING OF HIGH VOLTAGE GRADIENT ZnO-BASED THICK FILM VARISTORS

High voltage gradient ZnO-based thick film varistors were fabricated by low-temperature sintering. The effect of sintering temperature on electrical properties of thick film varistors was investigated. The voltage gradient of thick film varistors increased significantly to 3159.4 V/mm after sintering at 725°C for 30 min. The small average grain size with good grain boundaries was the origin for...