A Study of The Main Electrophysical Parameters of Semiconductor - Polymer Based Composite Varistors

Abstract

The main electrophysical parameters of composite varistors made on the basis of doped ZnO, monocrystalline Si, GaAs, InAs and various polymers were studied in this work. In the article, the sample preparation process is described, interphase interaction is discussed. The nonlinearity coefficient () and opening voltages (Uop) of volt-ampere characteristics in doped ZnO, monocrystalline Si ceramic semiconductors and polymer-based composite varistors were determined. The volt-ampere characteristics of monocrystalline Si, GaAs and InAs and polymer-based composites were also measured. The shape of the potential hole in the mentioned composites has been determined. It was found that the opening voltage and the nonlinearity of the volt-ampere characteristic of polymer-semiconductor composites mainly depend on the properties of the 3rd phase. According to the experiment, it was found that as the filler volume percentage increases in ZnO, monocrystalline Si, GaAs and InAs and polymer-based composites, the  increases in all samples, and the Uop decreases. Depending on the type of dispersant, the opening voltages of the composites are different. Thus, in ZnO-polymer-based composites with additives, this voltage varies between 130÷220 V, and in monocrystalline Si, GaAs and InAs and polymer-based composites, it varies between 5÷50 V. The analysis of the shape of the potential hole in composites based on monocrystalline Si, GaAs, and InAs has shown that the value of the forbidden zone in the composites decreases, and the value of the potential barrier decreases sharply.