Microscopic observation of interface structures of YBaCuO/MgO/YBaCuO double-heteroepitaxial thin films by TEM
Abstract
The YBaCuO/MgO/YBaCuO double-heterostructure (DHS) was fabricated using conventional RF magnetron sputtering. The formation of (110)YBaCuO/(100)MgO/(110)YBaCuO on (110)SrTiO3 substrate, and (001)YBaCuO/(100)MgO/(100)YBaCuO and (001)YBaCuO/(100)MgO/(001)YBaCuO on (100)MgO substrate are demonstrated. According to RHEED (refraction high-energy electron diffraction) observations, each layer of the DHS was grown epitaxially. The cross-sectional TEM (transmission electron microscope) observation of the (001)YBaCuO/(100)MgO(2 nm)/(001)YBaCuO structure was carried out in order to characterize the heterostructure. The ultrathin MgO layer grew in an island shape. The MgO shape deposited on YBaCuO film is island-like because of the low absorption energy of Mg on the YBaCuO surface and/or a large value of MgO/YBaCuO interface free energy. The YBaCuO atomic arrangement shape implied that the YBaCuO growth mechanism was atomic layer epitaxy.
- Publication:
-
IEEE Transactions on Magnetics
- Pub Date:
- March 1991
- DOI:
- 10.1109/20.133436
- Bibcode:
- 1991ITM....27.1361S
- Keywords:
-
- Epitaxy;
- High Temperature Superconductors;
- Magnetron Sputtering;
- Microstructure;
- Superconducting Films;
- Yttrium Oxides;
- Barium Oxides;
- Copper Oxides;
- Electron Diffraction;
- Magnesium Oxides;
- Mixed Oxides;
- Solid-State Physics