Preparation and characterization of Mg-doped CaCu3Ti4O12 thin films
(1. Key Laboratory of Metallurgical Emission Reduction & Resources Recycling, Ministry of Education, Anhui University of Technology, Ma’anshan 243002, China;
2. School of Materials Science and Engineering, Anhui Polytechnic University, Wuhu 241000, China;
3. China Innovation Academy of Intelligent Equipment (Ningbo) Co., Ltd., Ningbo 315700, China)
2. School of Materials Science and Engineering, Anhui Polytechnic University, Wuhu 241000, China;
3. China Innovation Academy of Intelligent Equipment (Ningbo) Co., Ltd., Ningbo 315700, China)
Abstract: Mg-doped CaCu3-xMgxTi4O12 (x=0, 0.05, 0.1, 0.15, 0.2, at.%) thin films were prepared by a modified sol-gel method. A comparative study on the microstructure and electrical properties of Mg-doped CaCu3Ti4O12 (CCTO) thin films was carried out. The grain sizes of the Mg-doped CCTO thin films were smaller in comparison to the undoped CCTO films. Furthermore, compared to undoped CCTO films, Mg-doped CCTO thin films obtained higher dielectric constant as well as excellent frequency stability. Meanwhile, Mg doping could reduce the dielectric loss of CCTO thin films in the frequency range of 104-106 Hz. The results showed that the Mg-doped CCTO thin films had the better electrical characteristics compared with the undoped CCTO films. The nonlinear coefficient of Mg-doped CCTO thin films at x=0.15 and x=0.1 was improved to 7.4 and 6.0, respectively.
Key words: dielectric material; CaCu3Ti4O12; Mg doping; dielectric constant; dielectric loss; varistor properties