Preparation and properties of low-temperature co-fired ceramic of CaO-SiO2-B2O3 system

Low temperature co-fired ceramic (LTCC) was prepared by sintering a glass selected from CaO SiO2 - B2O3 system, in which 0.5 wt% P2O5 and 0.5 wt% ZnO were added to optimize the preparation conditions. The glass powder and sintered bodies were characterized by different analytical techniques such as TG-DTA analysis, X-ray diffraction and Scanning electron microscopy. It was found that the optimal sintering temperature was 820 degrees C based on the microstructure and the properties of sintering bodies, and then the major phases of the LTCC were CaSiO3, CaB2O4 and SiO2. The obtained products, with dielectric constant about 6.5, dielectric loss about 2 x 10(-3) at 30 MHz and coefficient of thermal expansion about 8 x 10(-6) degrees C-1 between 20 and 400 degrees C, are supposed to be suitable for application in wireless communications.