Defects and Impurities Influences on Phase Transformations in Rare-Earth Oxides

摘要: Several types of defects are observed on thin films (up to 2500 A) pure rare-earth oxides type A-Ln2 O3 and B-Ln2O3. They (a) structural steps connected with the layered character structures which contain (LnO)n n+ entities parallel thin-film surface, (b) reciprocal twins in B-Ln2 I [twin plane (313)] II axis (132)] whose combination yields microtwinned zones; (c) planar defects; (d) dislocations; possibly (e) antiphase boundaries. The twinning is directly seen, under electron microscope, securing syntaxy conditions between two phases when A → or B transition takes place. small amount yttrium A-Nd2 induces formation domains B-Nd2 O3. transformation is, from X-ray investigation, complete at 10 atomic percent yttrium, consequently phase stabilized. An microscopy investigation mixed containing up suggests possibility that microdomains C-Ln2 operative O3, can be produced by a mechanical stress. well-defined epitaxy C was determined films.