THE ORIENTED GROWTH OF PBTIO3 THIN-FILMS DEPOSITED BY A SOL-GEL PROCESS ON SUBSTRATES WITHOUT LATTICE MATCH

PbTiO3 thin films were deposited by a sol-gel process onto various sub strates without lattice match and their preferred orientations were in vestigated. Preferentially a axis-oriented films were obtained on Si(1 11) and quartz glass. The films on r-sapphire exhibited a highly prefe rred orientation along both the (101) and the (110) axes. Both a and c axis-oriented PbTiO3 thin films were prepared on (111) Pt-coated Si s ubstrates. It is demonstrated that the films fired at lower temperatur es are difficult to align with the substrates. The degree of grain ori entation of thicker films is lower than that of thin films. The origin of the orientations found in our thin films is discussed. However, th e mechanism by which nuclei of the orientations form at the film/subst rate interface is not yet known.