Microwave Dielectric Properties of (Mg0.95Ni0.05)TiO3-SrTiO3 Ceramics with a Near-Zero Temperature Coefficient of Resonant Frequency

• Published in: International journal of applied ceramic technology Vol. 7; no. 2; pp. 207 - 216
• Main Authors: Shen, Chun-Hsu, Huang, Cheng-Liang
• Format: Journal Article
• Language: English
• Published: Malden, USA Blackwell Publishing Inc 01.03.2010
• Subjects: Aluminum oxide; Bandpass filters; Ceramics; Dielectric constant; Dielectric properties; Dielectrics; Microwaves; Strontium titanates
• ISSN: 1546-542X; 1744-7402
• DOI: 10.1111/j.1744-7402.2008.02352.x

The microwave dielectric properties of a (1−x)(Mg0.95Ni0.05)TiO3–xSrTiO3 ceramics system were investigated. The system was prepared using a conventional solid‐state ceramic method. To produce a temperature‐stable material, SrTiO3 was added, which led to a near‐zero temperature variation in resonant frequency. The variation in microwave dielectric properties of the (1−x)(Mg0.95Ni0.05)TiO3–xSrTiO3 ceramics system significantly depends on the amount of SrTiO3 present. As x was varied from 0.01 to 0.1, the microwave Q×f value decreased from 105,000 to 31,000 GHz and the dielectric constant (ɛr) increased from 18.74 to 26.5. A microwave dielectric material with a dielectric constant (ɛr) of 21, a Q×f value of 73,000 GHz, and a τf value of 1 ppm/°C were obtained from the compound 0.96(Mg0.95Ni0.05)TiO3–0.04SrTiO3 sintered at 1300°C for 4 h. To verify the performance of the 0.96(Mg0.95Ni0.05)TiO3–0.04SrTiO3 ceramics, a band‐pass filter with traditional hairpin resonators was designed and simulated on different dielectric materials [such as FR4, alumina, and 0.96(Mg0.95Ni0.05)TiO3–0.04SrTiO3].