Interpretation of Cu(111)//Nb(110) growth on SiO2 by Transmission Electron Microscopy

The [110]-textured extremely thin Nb barrier layer is prepared on an amorphous SiO₂ substrate, on which the preferentially oriented Cu [111] texture is obtained. Transmission Electron Microscopy (TEM) observation indicates that nanocrystalline grains no larger than ~10 nm with a spread [110] orientation along the substrate normal direction is characteristic of a 10 nm thick Nb barrier on SiO₂, whereas for the 100 nm thick barrier, the well-oriented columnar structure of a Nb [110] layer is obtained by ordering the orientation during the increase in the thickness of the Nb film by the coalescence of the initially deposited nanocrystalline grains. The quality of Cu [111] layer is much better when deposited on 100 nm thick Nb layer than that on a 10 nm thick barrier.