title: Fabrication of modified lead titanate piezoceramics with zero temperature coefficient and its application on SAW devices.
abstract: The Samarium-modified, lead titanate ceramics with a composition of (Pb0.67Ca0.15Sr0.06Sm0.08) (Ti0.98Mn0.02)O3 were prepared by conventional mixed-oxide method. By properly varying the sintering and poling conditions, the samples with zero temperature coefficient of resonant frequency were fabricated. The piezoelectric and dielectric properties were measured; it showed that the samples with zero temperature coefficient still keep high-thickness, electromechanical coupling coefficient, kt (>0.55), and small planar electromechanical coupling coefficient, kp. Surface acoustic wave (SAW) filters were fabricated; and the properties, including phase velocity and electromechanical coupling coefficient, were measured. Microstructural and compositional analyses have been carried out using scanning electron microscopy and x-ray diffraction.
authors.affiliation: Department of Electrical Engineering, National Cheng Kung University, Tainan, Taiwan. chusy@mail.ncku.edu.tw
authors.forename: Sheng-Yuan
authors.initials: SY
authors.lastname: Chu
authors.forename: Te-Yi
authors.initials: TY
authors.lastname: Chen