Effects of composition tailoring on structure and microwave dielectric characteristics of SrSmAlO4 ceramics

✍ Scribed by M.M. Mao; X.C. Fan; X.M. Chen

• Book ID: 104022898
• Publisher: Elsevier Science
• Year: 2008
• Tongue: English
• Weight: 749 KB
• Volume: 28
• Category: Article
• ISSN: 0955-2219
• DOI: 10.1016/j.jeurceramsoc.2008.03.031

✦ Synopsis

Effects of composition tailoring on the microwave dielectric characteristics of SrSmAlO 4 ceramics were investigated together with the structure. K 2 NiF 4 -type major phase with minor amount of secondary phases was observed in the modified ceramics with nominal composition Sr 1+x Sm 1-x AlO 4-x/2 (x = -0.05, -0.025, 0.025, 0.05), and the type of secondary phase is dependent on x. Sr 2.25 Sm 0.75 AlO 4.875 secondary phase is detected for x > 0, while the secondary phase for x < 0 is SrSm 2 Al 2 O 7 . Though the accurate stoichiometric composition is very important to guarantee the highest Qf value, it is an effective way to adjust the temperature coefficient of resonant frequency τ f by tailoring composition. τ f can be adjusted from negative to positive by varying x from 0 to -0.05, while more negative τ f can be achieved by varying x from 0 to 0.05. Suitable modified composition with x < 0 is also desired for obtaining high Qf value and small τ f with the controlled sensitivity to sintering temperature.