Origin of Orientation in Sol‐Gel‐Derived Lead Titanate Films

The origin of orientation in sol‐gel‐derived PbTiO 3 films is investigated in detail. Aging of the solution is found to promote (100) orientation of the films. Characterizing the solution by viscometry indicates that the preferred orientation might be attributable to the change of molecular size in the solution. The substrate also influences the film orientation: more strongly (100)‐oriented film forms on Pt‐coated Si than on fused quartz. Highly c ‐axis‐oriented films with azimuthal orientation are grown on a (100) SrTiO 3 single‐crystal disk.