A high surface area is important to prevent electric run away. Extensive work has already been done.
After sintering surface uniformity and thickness of the films were observed under the Optical and Electron Microscopes. No defects were observed and the thickness of the films varied from 10 to 100 microns.
The increase in dielectric constant with sintering temperature is believed to be associated with the increase in film density and in the improvement in film adherence/bonding to the metal electrodes.