The dielectric properties at microwave frequencies and the microstructures
of BiTaO4 ceramics with 0.5 wt.% doping of CuO have been investigated. The
BiTaO4 ceramics can be sintered to approach 95% theoretical density at 960
degrees C. Sintered ceramic samples were characterized by X-ray and scannin
g electron microscopy (SEM). The dielectric constant values (epsilon(r)) sa
turate at 44-45. The Q X f values of 8000-12 000 (at 6 GHz) can be obtained
when the sintering temperatures are in the range of 920-960 degrees C. The
temperature coefficient of resonant frequency tau(f) was -40 ppm/degrees C
. The BiTaO4 ceramics have applications for multilayer microwave devices re
quiring low sintering temperatures. (C) 2000 Elsevier Science B.V. All righ
ts reserved.