Growth of high crystalline quality thin epitaxial CeO2 films on (1(1)over-bar-02) sapphire

We have prepared (001) oriented epitaxial CeO2 films on (1102)sapphire by m etal organic chemical vapour deposition. The film thickness was in the rang e from 10 to 100 run. The films exhibit extremely degree of preferred orien tation, having half width at half maximum (FWHM) values of the X-ray diffra ction rocking curve of the (002) CeO2 reflection as low as 0.05 degrees. Th is value is comparable to the FWHM of the rocking curve of the single cryst al. We show the evolution of CeO2 the film rocking curve as a function of t he thickness, deposition temperature and quality of die substrate. These re sults are compared with atomic force microscopy images of the film surface. A possible mechanism of the growth of CeO2 films exhibiting narrow peak of the rocking curve is discussed.