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The deposition of alternating (sub)monolayers of lanthanum oxide (La2O3) and zirconium oxide (ZrO2) by atomic layer deposition has been carried out to create uniform LayZr1-yOx mixed oxide films. However, spontaneous nucleation of ZrO2 nanocrystals occurs during deposition within an amorphous La2O3 matrix. Such ZrO2 embedded La2O3 films exhibit low leakage currents in combination with higher electric breakdown fields and higher dielectric permittivities than the pure lanthanum and zirconium oxide films. The possible scenarios that account for this enhanced electric performance of these nanocluster-embedded dielectric thin films are explained. [ABSTRACT FROM AUTHOR]

During atomic layer deposition of homogeneous LayZr1-yOx thin films spontaneous segregation of ZrO2 nanocrystals that are embedded in an amorphous La2O3 matrix takes place. This occurs if the Zr content in the LayZr1-yOx film rises above 30%, i.e., if the pulse ratio between the lanthanum precursor and the zirconium precursor is larger than four. X-ray diffraction analysis shows that the ZrO2 nanocrystals are in the tetragonal phase, which is the most stable configuration of this material with the highest dielectric permittivity. These nanocrystal-embedded thin films exhibit higher dielectric constants as the Zr content increases. [ABSTRACT FROM AUTHOR]