EFFECTS OF THERMAL ETCHING CONDITIONS ON SEM OBSERVATIONS OF TWO KINDS OF BaTiO3-BASED CERAMICS

Yongshun Zheng, Dayong Lu

ABSTRACT:The effects of thermal etching temperature (Tte) and time (tte) on scanning electron microscope (SEM) observations were investigated using X-ray diffraction (XRD), SEM, backscattered electron (BSE), and dielectric measurements for (Ba1−xMgx) TiO3 (x = 0.015) (BMT) and BETC (not open) ceramics prepared at the sintering temperatures of Ts = 1200 °C and 1400 °C, respectively. BMT and BETC exhibit a pseudo-cubic and a tetragonal perovskite structures, respectively. When Tte > Ts, the crystalline structure, microstructure and dielectric thermal properties change, and at this time the observed SEM image cannot reflect the real morphology of BMT. The Tte should be equal to or less than Ts. An optimum condition for clear SEM observations of BETC was determined to be Tte = 1400 °C for Tte = 18 min, and at this time, the crystalline structure and dielectric properties of BETC did not change. Under a given thermal etching temperature, the thermal etching time has a great influence on the SEM image quality of sample

Keywords:BaTiO3 ceramics, scanning electron microscope, microstructure, X-ray diffraction, dielectric properties