Morphology of crystalline structure and atomic bonds inside DyxOy films grown on Si

It is well known that the formation of crystalline grains in the dielectric films leads to oxygen diffusion along grain boundaries during thermal processing. This can result in the growth of interfacial SiOx layer and increase the possible equivalent SiO2 thickness that should have the high-k materials. Moreover, the grain boundary diffusion of other impurities deteriorates the electrical performance of the MOS devices. Among the high-k dielectrics under study, DyxOy appears promising due to its relatively high dielectric constant (k = 12) as compared to SiO2 (k = 3.9). Therefore, we have studied the crystalline structure and the surface morphology of the thin DyxOy films grown on Si as a function of the growth conditions. To examine the crystalline structure and range of ordering in DyxOy layers prepared at different conditions the synchrotron radiation diffraction and absorption was used. To study the roughness and morphology of the surface and interface AFM was employed. The paper presents results of these studies