TRANSMISSION ELECTRON-MICROSCOPY INVESTIGATION OF BIAXIAL ALIGNMENT DEVELOPMENT IN YSZ FILMS FABRICATED USING ION-BEAM-ASSISTED DEPOSITION

Detailed microstructural development of biaxially aligned yttria-stabi lized zirconia (YSZ) films fabricated using ion beam assisted depositi on is reported for the first time. The YSZ films in this study were de posited by ion beam assisted deposition onto Pyrex substrates. a colum nar microstructure was exhibited in all the films studied. There are t hree populations of columns with (001) azimuthal orientation in the fi lm microstructure. The (001) YSZ columns have a faceted dendritic micr ostructure, consistent with atom attachment at (101) layer source plan es during growth from the vapor. Selected area electron diffraction fr om cross-sectional specimens indicates that most of the biaxial alignm ent is achieved within 100 nm of the substrate, with little improvemen t thereafter. The microstructural development of biaxial alignment is consistent with a previously proposed model involving anisotropic grow th and extinction of the YSZ columns during ion beam assisted depositi on. (C) 1996 American Vacuum Society.