Effect of sintering temperature and time on microwave dielectric properties of lanthanum tin oxide

• Published in: Journal of materials science. Materials in electronics 2013-06, Vol.24 (6), p.1878-1882
• Main Authors: Chen, Yih-Chien, Chen, Kuei-Chien, Lee, Wei-Cheng
• Format: Article
• Language: English
• Subjects: Applied sciences; Ceramics; Characterization and Evaluation of Materials; Chemistry and Materials Science; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Density; Dielectric constant; Dielectric properties; Dielectric properties of solids and liquids; Dielectrics, piezoelectrics, and ferroelectrics and their properties; Electronics; Exact sciences and technology; Materials; Materials Science; Microwaves; Optical and Electronic Materials; Permittivity (dielectric function); Physics; Quality factor; Sintering; Tin oxides
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-012-1028-7

This study examines the microwave dielectric properties of La 2 Sn 2 O 7 ceramics with a view to the use of these ceramics in mobile communication. La 2 Sn 2 O 7 ceramics were prepared by the conventional solid-state method with various sintering temperatures and times. The highest density obtained, 6.61 g/cm 3 , was that of La 2 Sn 2 O 7 ceramic that was sintered at 1,580 °C for 34 h. Dielectric constants ( ε r ) of 13.2–14.4 and quality factors ( Q  ×  f ) of 34,300–40,500 GHz were obtained by sintering at temperatures in the range 1,520–1,610 °C for 34 h. Dielectric constants ( ε r ) of 10.3–14.4 and quality factors ( Q  ×  f ) of 15,300–40,500 GHz were obtained using sintering times of 30–38 h at a sintering temperature of 1,580 °C. When La 2 Sn 2 O 7 was sintered at 1,580 °C for 34 h, a dielectric constant ( ε r ) of 14.4, a quality factor ( Q  ×  f ) of 40,500 GHz and a temperature coefficient of resonant frequency ( τ f ) of −54 ppm/ °C were obtained.