Title :
Preparation, structure and dielectric properties of bismuth-based ceramic dielectrics
Author :
Hong, WANG ; Xiaoli, WANG ; Xi, Yao
Author_Institution :
Electron. Mater. Res. Lab., Xi´´an Jiaotong Univ., China
Abstract :
Samples of 0.75Bi2O3-ZnO-0.75A2O 5 (A=Nb, Ta) were prepared by conventional ceramic technology, sintered below 1000°C. Based on X-ray diffraction analysis, the structure of 0.75Bi2O3-ZnO-0.75Nb 2O5 (BZN) composition is characterized as cubic pyrochlore, while the 0.75Bi2O3-ZnO-0.75Ta2 O5 (BZT) composition is a multiphase ceramic with two cubic fluorites and an orthorhombic pyrochlore structures. The bismuth-based ceramic dielectrics have excellent electrical resistivity greater than 1014 ohm-cm. The BZN dielectric has dielectric constant around 130, the room temperature dissipation factor is less than 4×10-4 from 10 KHz to 1 MHz, and the temperature coefficient of the dielectric constant is about -470 ppm/°C. For the BZT composition, the dielectric constant decreases to 80, the dissipation factor deteriorates to 5×10-3, and the temperature coefficient increases to +60 ppm/°C
Keywords :
X-ray diffraction; bismuth compounds; ceramics; crystal structure; dielectric losses; electrical resistivity; niobium compounds; permittivity; sintering; tantalum compounds; zinc compounds; 0.75Bi2O3-ZnO-0.75Nb2O5 ; 0.75Bi2O3-ZnO-0.75Ta2O5 ; 10 kHz to 1 MHz; 1000 C; 1E14 ohmcm; BZN composition; BZT composition; Bi-based ceramic dielectrics; Bi2O3-ZnO-Nb2O5; Bi2O3-ZnO-Ta2O5; X-ray diffraction analysis; ceramic technology; cubic fluorites; cubic pyrochlore structure; dielectric constant; dielectric properties; electrical resistivity; multiphase ceramic; orthorhombic pyrochlore structure; preparation; room temperature dissipation factor; sintering; temperature coefficient of dielectric constant; Ceramics; Consumer electronics; Dielectric constant; Dielectric materials; Dielectric measurements; Electric resistance; Laboratories; Lattices; Temperature; Zinc oxide;
Conference_Titel :
Electrets, 1996. (ISE 9), 9th International Symposium on
Conference_Location :
Shanghai
Print_ISBN :
0-7803-2695-4
DOI :
10.1109/ISE.1996.578252
