Effect of B₂O₃ Additions and Sintering Temperature on the Microwave Dielectric Properties of 0.7La(Mg_0.5Sn_0.5)O₃–0.3(Sr_0.8Ca_0.2)₃Ti₂O₇ Ceramics

Abstract

The microwave dielectric properties of 0.7La(Mg_0.5Sn_0.5)O₃–0.3(Sr_0.8Ca_0.2)₃Ti₂O₇ ceramics were investigated for application in mobile communication. A sintering temperature reduction of about 150°C was obtained by using B₂O₃ as sintering aid. The X-ray diffraction patterns of the 0.7La(Mg_0.5Sn_0.5)O₃–0.3(Sr_0.8Ca_0.2)₃Ti₂O₇ ceramics exhibited no significant variation of phase with extent of B₂O₃ addition and sintering temperatures. The dielectric constant, quality factor, and temperature coefficient of resonant frequency of 0.7La(Mg_0.5Sn_0.5)O₃–0.3(Sr_0.8Ca_0.2)₃Ti₂O₇ ceramics doped with 0.50 wt% B₂O₃ addition sintered at 1400°C for 4 h are 30.0, 28,800 GHz, and 0 ppm/ ^OC, respectively.

Keywords:

• La(Mg_0.5Sn_0.5)O₃-(Sr_0.8Ca_0.2)₃Ti₂O₇
• Dielectric constant
• Quality factor
• Temperature coefficient of resonant frequency

Acknowledgment

This work was supported by the National Science Council of the Republic of China under Grant NSC 98-2622-E-262-003-CC3.

Communicated by Dr. George W. Taylor