C. Metzmacher et K. Albertsen, Microstructural investigations of barium titanate-based material for base metal electrode ceramic multilayer capacitor, J AM CERAM, 84(4), 2001, pp. 821-826
The microstructures of BME-X7R ceramics have been investigated by imaging a
nd analytical TEM, By varying the sintering conditions (pressing, sintering
temperature and atmosphere), the microstructure changes drastically, and d
islocation loops can be observed. These defects most probably are caused by
an ordering of oxygen vacancies in the lattice, and the density appears to
be correlated to the oxygen partial pressure applied during the reoxidatio
n step. For pressed and unpressed ceramic foils, a model for different sint
ering behaviors according to liquid-phase assistance is given that is based
on a kinetically determined microstructure rather than thermodynamic equil
ibrium.