Relaxation peaks of ZnO varistors and their correlations with electrical properties

2021 ◽  
Vol 60 (3) ◽  
pp. 031006
Author(s):  
Xia Zhao ◽  
Weidong Shi ◽  
Boyu Zhang ◽  
Men Guo ◽  
Haibin Shen
Keyword(s):  
Electrical Properties ◽  
Zno Varistors

scholarly journals Microstructure and Electrical Properties of Low-Voltage Barium Titanate Doped Zinc Oxide Varistor Ceramics

2019 ◽  
Vol 8 (4) ◽  
pp. 2713-2718
Keyword(s):  
Zinc Oxide ◽  
Electrical Properties ◽  
Barium Titanate ◽  
Grain Boundary ◽  
Barrier Height ◽  
Current Density ◽  
Low Voltage ◽  
X Ray ◽  
Highly Nonlinear ◽  
Zno Varistors

In the present, varistor ceramics through the combination of zinc oxide (ZnO) with a perovskite material have become widespread because of their unique properties for a wide range of applications in electronic protection devices. Low-voltage zinc oxide (ZnO) varistors with fast response and highly nonlinear electrical properties for overvoltage protection in an integrated circuit are increasingly significant in the application of low-voltage electronics. The present study highlights the interaction between barium titanate (BaTiO3 ) and ZnO varistors through the employment of solid-state reaction method in the production of low-voltage varistors. The effects of BaTiO3 on the microstructure of ZnO varistors were analyzed through scanning electron microscopy (SEM), energy dispersive X-ray analysis spectroscopy (EDS) and X-ray diffraction (XRD). The EDS analysis and XRD measurements suggest the presence of ZnO and BaTiO3 phases. The electrical properties of BaTiO3 -doped ZnO varistors were examined based on the current density-electric field (J-E) characteristics measurement. The varistor properties showed the nonlinear coefficient (α) from 1.8 to 4.8 with the barrier height (φB) ranged from 0.70 to 0.88 eV. The used of BaTiO3 additive in ZnO varistors produced varistor voltages of 4.7 to 14.1 V/mm with the voltage per grain boundary (Vgb) was measured in the ranges 0.03 to 0.05 V. The lowest leakage current density was 348 µA/cm2 , obtained at the samples containing 12 wt.% BaTiO3 with high barrier height. The reduction in barrier height with increasing BaTiO3 content was associated with the excessive amount of BaTiO3 phase, hence cause the deterioration of active grain boundary due to the variation of oxygen (O) vacancies in the grain boundary.

scholarly journals Revisiting the effects of Co 2 O 3 on multiscale defect structures and relevant electrical properties in ZnO varistors

High Voltage ◽  
2020 ◽  
Vol 5 (3) ◽  
pp. 241-248 ◽  
Author(s):  
Men Guo ◽  
Yao Wang ◽  
Kangning Wu ◽  
Lei Zhang ◽  
Xia Zhao ◽  
...  
Keyword(s):  
Electrical Properties ◽  
Defect Structures ◽  
Zno Varistors

Effects of SiO2/Cr2O3 ratios on microstructures and electrical properties of high voltage gradient ZnO varistors

2019 ◽  
Vol 30 (13) ◽  
pp. 12113-12121 ◽  
Author(s):  
Xuejun Ruan ◽  
Xin Ren ◽  
Wenting Zhou ◽  
Xi Xu ◽  
Xin Wang ◽  
...  
Keyword(s):  
Electrical Properties ◽  
High Voltage ◽  
Voltage Gradient ◽  
Zno Varistors

Electrical Properties of Microwave-Sintered ZnO Varistors

1999 ◽  
Vol 38 (Part 1, No. 9B) ◽  
pp. 5500-5504 ◽  
Author(s):  
Wan-Chui Lee ◽  
Kuo-Shung Liu ◽  
I-Nan Lin
Keyword(s):  
Electrical Properties ◽  
Zno Varistors

Effect of Technological Parameters on the Microstructure and Electrical Properties of ZnO Varistors

2013 ◽  
Vol 820 ◽  
pp. 208-211
Author(s):  
Li Li ◽  
Qi Bin Liu
Keyword(s):  
Solid State ◽  
Electrical Properties ◽  
Leakage Current ◽  
Sintering Temperature ◽  
Voltage Gradient ◽  
Technological Parameters ◽  
Reaction Route ◽  
Conventional Solid State Reaction ◽  
Zno Varistors ◽  
Solid State Reaction Route

To improve voltage-gradient and to reduce the sintering temperature of ZnO varistors, high voltage-gradient ZnO varistors were synthesized with a conventional solid state reaction route. By means of SEM and DC parameter instrument for varistor, the influence of different technological parameters on microstructure, voltage-gradient and leakage current of ZnO varistors was investigated. The experimental results show that by using the process that presintering the additives at 850°C, the density is improved, the voltage-gradient is increased, and the leakage current is decreased. The optimum voltage-gradient and leakage current are 371V/mm and 3μA, respectively.

The Effects of Cu Dopant on the Microstructure and Non-Ohmic Electrical Properties of ZnO Varistors

2011 ◽  
Vol 343-344 ◽  
pp. 160-165 ◽  
Author(s):  
Ji Wei Fan ◽  
Xiao Peng Li ◽  
Zhen Guo Zhang ◽  
Zhi Qiang Jiao ◽  
Xiang Yang Liu ◽  
...  
Keyword(s):  
Electrical Property ◽  
Electrical Properties ◽  
Grain Boundary ◽  
Grain Growth ◽  
Electrical Characteristics ◽  
Doping Effects ◽  
Zno Varistors ◽  
Doped Zno ◽  
Cu Dopant ◽  
Good Agreement

The doping effects of Cu on the microstructure and non-ohmic electrical properties of ZnO varistors were studied. Addition of Cu2O can enhance the ZnO grain growth during sintering. The SEM and EDS results revealed that the added Cu mainly distributed in the grain boundary and spinel phases of ZnO varistors. The Cu2O addition increased the both of grain and grain boundary resistances. However it decreased the non-ohmic electrical characteristics of ZnO varistors, which is a good agreement with similar findings on Ag2O additions, but contrasts to the reports of good non-ohmic electrical property which found on binary Cu doped ZnO varistors.

Electrical Properties of ZnO-Bi2O3 Metal Oxide Heterojunction — A Clue of a Role of Intergranular Layers in ZnO Varistors

1981 ◽  
Vol 5 ◽  
Author(s):  
Kazuo Eda
Keyword(s):  
Thin Film ◽  
Electrical Properties ◽  
Metal Oxide ◽  
Oxide Thin Film ◽  
Thin Film Thickness ◽  
Metal Oxide Thin Film ◽  
Zno Varistors ◽  
Current Characteristics ◽  
Zno Ceramics

ABSTRACTZinc Oxide (ZnO) Ceramics-Bismuth Oxide (Bi2O3) Metal Oxide thin film heterojunction made by sputtering technique showed a highly non-Ohmic property. The voltage-current characteristics and the dielectric properties showed dependence on Bi2O3 metal oxide thin film thickness.In this paper after reviewing and discussing the electrical properties of ZnO varistors, the role of intergranular layers in the ZnO varistor is discussed based on experimental results with the heterojunction.

Influence of sintering temperature on electrical properties of ZnO varistors

1993 ◽  
Vol 74 (1) ◽  
pp. 695-703 ◽  
Author(s):  
Shr‐Nan Bai ◽  
Tseung‐Yuen Tseng
Keyword(s):  
Electrical Properties ◽  
Sintering Temperature ◽  
Zno Varistors

Preparation and Electrical Properties of Multilayer Zinc Oxide Varistor by Gelcasting

2014 ◽  
Vol 852 ◽  
pp. 285-290
Author(s):  
Mao Yan Fan ◽  
Li Fang Zhang ◽  
Hong Xiao ◽  
Tian Tian Xie
Keyword(s):  
Electrical Properties ◽  
Tape Casting ◽  
Optimum Concentration ◽  
Water Soluble ◽  
Solid Loading ◽  
High Solid Loading ◽  
Water Based ◽  
Zno Varistors ◽  
Zinc Oxide Varistor ◽  
Positive Effect

Multilayer ZnO varistors were prepared by aqueous gel tape casting with water-soluble acrylamide as binder. 0.8wt% PAA dispersant was found to be the optimum concentration needed to prepare stable slurry. Plasticizer glycerol has a positive effect on the fluidity of the suspension and oxygen anti-polymerizing inhibitor PEG 2000 deteriorated the fluidity. The addition of 15wt. % PEG2000 eliminates the surface exfoliation absolutely due to the oxygenation of ether units. The solid loading of the slurry was about 71wt% compared to the custom acrylic formulation binder 60wt%. The multilayer ZnO varistors prepared by aqueous gel tape casting display comparable good electrical properties to those prepared by water-based tape casting using custom acrylic formulation binder which is attributed to the high solid loading of slurry.

Sign in / Sign up

Export Citation Format

Share Document