Correlation between sintering pressure and electrical properties of hot-press sintered gallium arsenide-polyaniline-polyethylene composite varistors

GaAs-polymer composite varistors are prepared using hot pressing method at a temperature of 130 °C and different pressures and their current-voltage characteristics are investigated. The results show that these varistors can be used to protect circuits from 35 V up to 52 V over voltages. In addition, it is found that the varistor breakdown voltage and its nonlinearity as well as its impurity band gap increase by increasing sintering pressure while the corresponding barrier height decreases. Each sample has hysteresis which increases through the increase in sintering pressure. This causes the varistors to have lower lifetime due to their high degradation. These results are both investigated and analyzed using SEM micrographs.