Effect of sintering process on the electrical properties and microstructure of Ca-doped ZnO varistor ceramics. (October 2021)

• Record Type: Journal Article
• Authors: Wang, Hao; Zhao, Hongfeng; Liang, Wenxin; Fan, Shaohua; Kang, Jiashuang
• Is Part Of: Materials science in semiconductor processing. Volume 133(2021)
• Publication Date: 2021-10
• Subjects: ZnO -- Varistor ceramics -- Sintering temperature -- Electrical properties; Semiconductors -- Periodicals; Integrated circuits -- Materials -- Periodicals; Semiconducteurs -- Périodiques; Circuits intégrés -- Matériaux -- Périodiques; Electronic journals; 621.38152
• DOI: 10.1016/j.mssp.2021.105880
• Languages: English
• ISSNs: 1369-8001

Abstract

Abstract: The electrical properties of Ca-doped ZnO varistor ceramics are affected by sintering temperature. The samples exhibit excellent electrical properties and microstructure at a sintering temperature of 1050 °C. The ZnO varistor ceramics sintered at 950 °C have the best voltage gradient value, but their nonlinearity and leakage current are very poor. At different sintering temperatures, the grain boundary behavior of ZnO varistor ceramics is different. The grain boundary barrier increases with the increase in the surface state concentration, and it reaches the optimal value at the sintering temperature of 1050 °C. The electrical properties of the samples at the sintering temperature of 1050 °C are as follows: breakdown voltage E 1mA = 529 V/mm, leakage current J L = 0.13 μA/cm 2, and nonlinearity coefficient α = 92. High lights: (1) The sintering temperature affects the grain boundary layer resistance value noteworthily. (2) The optimal sintering temperature of Ca-doped ZnO varistor ceramics is 1050 °C. (3) The optimal electrical parameters are nonlinearity coefficient 92, voltage gradient 529 V/mm and leakage current 0.13 μA/cm 2 at 1050 °C.