Structure analysis of ceo₂/zro₂si multilayer thin films by hrtem

The dependence of the structures of the CeO₂/YSZ (Y₂O₃-ZrO₂/Si multilayer thin films on the YSZ thickness was investigated by HRTEM. The CeO/YSZ interface is semicoherent with misfit dislocations for the films with 110 nm and 30 nm YSZ thickness. On the other hand, the structure of the films with 0.5 nm YSZ layer are very muzzy since the YSZ is very disordered. However, the CeO₂ layer on the 0.5 nm of the YSZ has the lowest mosaicity (highest quality) near the surface, although once the epitaxy is weakened in the YSZ layer and the CeO₂ layer just above the YSZ. The mosaicity of the YSZ layer is thought not to be taken over into the CeO₂ layer since the columnar structure of the thinner YSZ layer becomes obscure. Moreover, a YSZ layer of only 0.5 nm could inhibit the reduction of CeO₂ by Si. The ultra thin YSZ layer of 0.5 nm is necessary because it inhibits the growth of the columnar structure and protects the protection of CeO₂ layer from reduction.